Answer:
a) $1,920
b) $9,920
Explanation:
Step 1. Gather all of the information.
The amount borrowed will be the principal or starting amount P:
[tex]P=8,000[/tex]The interest rate will be r:
[tex]r=4\text{ percent}[/tex]We will need the interest rate in decimal form, for that, divide the percentage amount by 100:
[tex]\begin{gathered} r=\frac{4}{100} \\ \downarrow \\ r=0.04 \end{gathered}[/tex]And the time of the loan is 6 years, this will be the value of t:
[tex]t=6[/tex]Step 2. To solve part a, we use the following formula to calculate the interest:
[tex]I=p\times r\times t[/tex]Substituting all of the known values:
[tex]I=8,000\times0.04\times6[/tex]The result is:
[tex]I=1,920[/tex]The total interest that Karen will have to pay is $1,920.
Step 3. To solve part b, we need to find the total repayment amount.
To find this, we add the interest and the principal amount:
[tex]T=P+I[/tex]Where T represents the total amount.
Substituting P and I:
[tex]\begin{gathered} T=8,000+1,920 \\ \downarrow \\ T=9,920 \end{gathered}[/tex]The total amount she will have to repay is $9,920.
Answer:
a) $1,920
b) $9,920
A triangular pyramid has a base shaped like an equilateral triangle. The legs of the equilateral triangle are all 5 millimeters long, and the height of the equilateral triangle is 4.3 millimeters. The pyramid's slant height is 3 millimeters. What is its surface area?
The surface area of the triangular base pyramid is 19.75 mm².
How to find the surface area of a pyramid?The surface area of a triangular pyramid is the sum of the area of the whole sides of the triangular pyramid.
Therefore,
Surface area of a triangular pyramid = base area + 1 / 2 (perimeter × slant height)
The base of the triangular pyramid is an equilateral triangle. An equilateral triangle has congruent sides.
Therefore,
base area = 1 / 2 × 5 × 4.3
base area = 10.75 mm²
Hence,
perimeter of the base = 5 + 5 + 5 = 15 mm
Surface area of a triangular pyramid = 10.75 + 1 / 2 (15 × 3)
Surface area of a triangular pyramid = 10.75 + 1 / 2(18)
Surface area of a triangular pyramid = 10.75 + 9
Surface area of a triangular pyramid = 19.75 mm²
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Find the surface area to the nearest tenth.19 m4536.5 m22268.2 m2O 238.8 m2477.5 m2
Answer:
Explanation:
The given solid is a sphere of radius 19m.
The surface area of a sphere is calculated using the formula:
[tex]A=4\pi r^2[/tex]Substitute 19 for r:
[tex]\begin{gathered} A=4\times\pi\times19^2 \\ =4536.46m^2 \\ \approx4536.5\; m^2 \end{gathered}[/tex]The surface area of the sphere to the nearest tenth is 4536.5 square mete.
Remember to write a let statement and answer the question. A collection of dimes abs quarters has a value of $1.35. List all possible combinations of dimes abs quarters.
Let d represents dimes and q represents quarter.
Note that a dime is 10 cent, which is same as one over ten, and a quarter is one over four
[tex]\begin{gathered} d=\frac{1}{10}=0.1 \\ q=\frac{1}{4}=0.25 \end{gathered}[/tex]Given that a collection of dimes abs quarters has a value of $1.35, then this can be represented as below:
[tex]0.1d+0.25q=1.35[/tex]Multiply through by 100 to get
[tex]\begin{gathered} 100\times0.1d+100\times0.25q=100\times1.35 \\ 10d+25q=135 \end{gathered}[/tex]To get the possible combinations of dimes and quarters, lets the try different values of that will satisfy the equation.
When q is 1,
[tex]\begin{gathered} 10d+25q=135 \\ q=1 \\ 10d+25(1)=135 \\ 10d+25=135 \\ 10d=135-25 \\ 10d=110 \\ d=\frac{110}{10}=11 \end{gathered}[/tex]Therefore, 11 dimes and 1 quarter abs is a possible combination
When q is 3
[tex]\begin{gathered} 10d+25(3)=135 \\ 10d+75=135 \\ 10d=135-75 \\ 10d=60 \\ d=\frac{60}{10} \\ d=6 \end{gathered}[/tex]Also, 6 dimes and 3 quarter abs is a possible combination
When q is 5
[tex]\begin{gathered} 10d+25(5)=135 \\ 10d+125=135 \\ 10d=135-125 \\ 10d=10 \\ d=\frac{10}{10} \\ d=1 \end{gathered}[/tex]Also, 1 dime and 5 quarter abs is a possible combination
When q is 7
[tex]\begin{gathered} 10d+25(7)=135 \\ 10d+175=135 \\ 10d=135-175 \\ 10d=-40 \\ d=\frac{-40}{10}=-4 \end{gathered}[/tex]Since negative answer was gotten for dimes, 7 quater wouldn't give any possible combination.
Hence, there are It can be found that there are there are three possible combinations, these are:
11 dimes and 1 quarter abs
6 dimes and 3 quarter abs
1 dime and 5 quarter abs
13. Use the appropriate percent growth todetermine how much money Lyra will have incach ofthe following situations:(a) How much money will Lyra have after 10years if she invests $5,000 at 4% interestcom-poundcl annually?(1) Suppose that Lyra is saving for retirement,and has saved up $20,000. If her retirementaccount earns 3% interest each year, howmuch will she save in 25 years?(o) How much mowy will yra have after 20years if she $5,000 33.5% interestcompoundedannully?(d) How much money will yr hawwur 10 yearsit she is $6,000 AL 15% interestcompounded quarterly?(E) how much money will lyra have after 10years if she invests $5,000 at 0.8% interestcompounded continuously?(F) compare your answer to (a) and (c). Whichone made more money?
Given:
(a) P = $5000
t = 10 years
r = 4%
(b) P = $20,000
t = 25 years
r = 3%
(c) P = $5000
t = 20 years
r = 3.5%
(d) P = $5000
t = 10 years
r = 1.5%
(e) P = $5000
t = 10 years
r = 0.8%
(f) Compare the result of (a) and (c).
Required:
(a) Find the amount when interest is compound annually.
(b) To find the total amount after 25 years.
(c) Find the amount when interest is compound annually.
(d) Find the amount when interest is compound quarterly.
(e) Find the amount when interest is compound continuously.
Explanation:
The compound interest formula is given as:
[tex]A=P(1+\frac{r}{n})^{nt}[/tex]Where p =principal amount
r = rate of interest
n = compound frequency
t = time period in years
(a)
[tex]undefined[/tex]Determine which of the following are true statements. Check all that apply.
Substitute in each inequality the given corresponding solution (x,y) and prove if it makes a true math expression:
1.
[tex]\begin{gathered} -5x-9y\ge60 \\ (-3,-5) \\ \\ -5(-3)-9(-5)\ge60 \\ 15+45\ge60 \\ 60\ge60 \end{gathered}[/tex]As 60 is greater than or equal to 60, (-3,-5) is a solution for the inequality.2.
[tex]\begin{gathered} 4x-3y>1 \\ (5,7) \\ \\ 4(5)-3(7)>1 \\ 20-21>1 \\ -1>1 \end{gathered}[/tex]As -1 isn't greater than 1, (5,7) is not a solution for the inequality3.
[tex]\begin{gathered} -10x+8y<12 \\ (-9,-10) \\ \\ -10(-9)+8(-10)<12 \\ 90-80<12 \\ 10<12 \end{gathered}[/tex]As 10 is less than 12, (-9,-10) is a solution for the inequality.4.
[tex]\begin{gathered} 9x+7y\le98 \\ (9,3) \\ \\ 9(9)+7(3)\le98 \\ 81+21\le98 \\ 102\le98 \end{gathered}[/tex]As 102 is not less than or equal to 98, (9,3) is not a solution for the inequalityAnswer parts a through E for the function shown below
Solution
We are given the function
[tex]f(x)=x^3+4x^2-x-4[/tex]First, Let us do the simplification or factorization
[tex]\begin{gathered} f(x)=x^2(x+4)-1(x+4) \\ f(x)=(x^2-1)(x+4) \\ f(x)=(x-1)(x+1)(x+4) \end{gathered}[/tex](a).
The coefficient of x^3 is positive
(b).
So basically, we set f(x) = 0 to get the x - intercepts
[tex]\begin{gathered} f(x)=(x-1)(x+1)(x+4) \\ (x-1)(x+1)(x+4)=0 \\ x=1,-1,-4 \end{gathered}[/tex]The x - intercepts are
[tex]x=1, -1, -4[/tex]The graph of f(x) is also given below
estimate 1/4% of 798
You have to multiple the whole number and the fraction if you don’t know how to do it
We need to find how much spare represents the given space for vegetables.
The total are is 24 square feet and she will use 3/4 of the space for vegetables.
Then, you need to multuply the result by 3 and then, we need to divide 24 by 4.
Therefore:
24*(3/4) =72/4 = 18
Hence, she will use 18 square feet for vegetables.
given the function m(a)=27a^2+51a find the appropriate values:
solve m(a)= 56
a=
A function is a relationship between inputs where each input is related to exactly one output.
The value of a when m(a) = 56 is 7/9.
What is a function?A function is a relationship between inputs where each input is related to exactly one output.
We have,
m(a) = 27a² + 51a ____(1)
m(a) = 56 ____(2)
From (1) and (2) we get,
56 = 27a² + 51a
27a² + 51a - 56 = 0
This is a quadratic equation so we will factorize using the middle term.
27a² + 51a - 56 = 0
27a² + 71a - 21a - 56 = 0
(9a−7) (3a+8) = 0
9a - 7 = 0
9a = 7
a = 7/9
3a + 8 = 0
3a = -8
a = -8/3
We can not have negative values so,
a = -8/3 is neglected.
Thus,
The value of a when m(a) = 56 is 7/9.
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A motorboat takes 3 hours to travel 108 miles going upstream. The return trip takes 2 hours going downstream. What is the rate in still water and what is the rate of the current?Rate of the boat in still water: mi/hRate of the current: mi/hmi/h= miles per hour
Given:
It takes the boat 3 hours to travel 108 miles going upstream
Return trip = 2hours going downstream
Distance, d = 108 miles
Time going upstream = 3 hours
Time going downstream = 2 hours
Let's find the rate in still water and the current rate.
Let s represent the still rate
Let c represent the current rate.
Apply the distance formula:
Distance = Rate x Time
We have the set of equations:
(s - c) x 3 = 108.................................Equation 1
(s + c) x 2 = 108.................................Equation 2
Apply distributive property:
3s - 3c = 108
2s + 2c = 108
Let's solve both equations simultaneously using substitution method.
Rewrite the first equation for s:
3s - 3c = 108
Add 3c to both sides:
3s - 3c + 3c = 108 + 3c
3s = 108 + 3c
Divide all terms by 3:
[tex]\begin{gathered} \frac{3s}{3}=\frac{108}{3}+\frac{3c}{3} \\ \\ s=36+c \end{gathered}[/tex]Substitute s for (36 + c) in equation 2:
2s + 2c = 108
2(36 + c) + 2c = 108
72 + 2c + 2c = 108
72 + 4c = 108
Subtract 72 from both sides:
72 - 72 + 4c = 108 - 72
4c = 36
Divide both sides by 4:
[tex]\begin{gathered} \frac{4c}{4}=\frac{36}{4} \\ \\ c=9 \end{gathered}[/tex]Substitute c for 9 in either of thee equation.
Take the first equation:
3s - 3c = 108
3s - 3(9) = 108
3s - 27 = 108
Add 27 to both sides:
3s - 27 + 27 = 108 + 27
3s = 135
Divide both sides by 3:
[tex]\begin{gathered} \frac{3s}{3}=\frac{135}{3} \\ \\ s=45 \end{gathered}[/tex]Thus, we have the solutions:
c = 9
s = 45
The rate of boat in still water is 45 miles per hour
The rate of the current is 9 miles per hour
Therefore, we have:
Rate of boat in still water: 45 mi/h
Rate of current: 9 mi/h
Take the firs
ANSWER:
Rate of boat in still water: 45 mi/h
Rae of the current: 9 mi/h
Look at the figure below. 8 8 4 4 Which expression can be evaluated to find the area of this figure?
Answer
[tex]8^2-4^2[/tex]Step-by-step explanation
The figure consists of a square with sides of 8 units from which a square of sides of 4 units has been subtracted.
The area of a square is calculated as follows:
[tex]A=a^2[/tex]where a is the length of each side.
Substituting a = 8, the area of the bigger square is:
[tex]A_1=8^2[/tex]Substituting a = 4, the area of the smaller square is:
[tex]A_2=4^2[/tex]Finally, the area of the figure is:
[tex]A_1-A_2=8^2-4^2[/tex]When nee, a standard tire has 10/32 inches of tread. When only 2/32 inches of tread remains, tire needs to be replaced. If this occurs after 40,000, what thickness of tire rubber is lost every 1,000 miles driven? Answer in fractions of an inch.
Given:
A standard tire has 10/32 inches of tread.
The tire needs to be replaced when only 2/32 inches of tread remains left.
Here the tire is needed to be replaced after 40,000 miles.
To find:
The thickness of tire rubber lost every 1,000 miles.
Step-by-step solution:
According to the question,
The tire is replaced when only 2/32 inches of tread remain left.
The new tire has 10/32 inches of tread.
Thus tire needs to loose:
10/32 - 2/32 = 8/32 inches of tread.
This means upon traveling for 40,000 miles, 8/32 inches of tread is lost.
So their ratio equals:
40,000 = k (8/32)
k = 40,000 × 32 / 8
k = 40,000 × 4
k = 1,60,000
So to calculate for 1000 miles:
1000/x = 1,60,000
1/x = 1,60,000 / 1000
1/x = 160
x = 1 / 160 inches
Thus we can say for every 1000 miles, 1 / 160 inches of tread is lost.
Solve the method.simultaneous equation by graphicaly + 3x = 6y - 2x = 1
The equations given are
[tex]\begin{gathered} y+3x=6............1 \\ y-2x=1............2 \end{gathered}[/tex]The graph of the equations will be shown below
Hence, the solution to the equations is the point where the two equations intersect.
Therefore, the solution is
[tex](1,3)[/tex]Jordan owns a house painting service. For each house, they charge $95 plus $60 per hour of work. A linear equation that expresses the total amount of money Jordan earns per house is y=60x+95. What are the independent and dependent variables? What is the y-intercept and the slope?
Answer:
The slope is 60
The y intercept is 95
The independent variable is x (the number of hours)
The dependent variable is y (The amount earned.)
Step-by-step explanation:
Which list orders the numbers from least to greatest?
[tex]\pi \: 4.3 \: 3.6 \: 13 \: \sqrt{19} [/tex]
Answer:
[tex]\pi[/tex], 3.6, 4.3, [tex]\sqrt{19}[/tex], 13
Step-by-step explanation:
[tex]\pi[/tex]≈ 3.14 This is an approximation because [tex]\pi[/tex] never repeats or terminates.
[tex]\sqrt{19}[/tex] This is also a number that never repeats or terminates. If you put this in your calculator, I estimated it to
4.359
Using this information, I put the numbers in order.
Answer For Brainiest!
What 3D Objects' do EACH Net Make?
Looking at the 4th net, we see it has what seems to be 4 squares in a line. And two of them are each one united into another square.
Then, when we join the left side of the left square and the right side of the right square, we obtain a 3D object with 4 square faces, and 2 empty faces also in the form of a square.
After that, we can fold down the upper square face, and fold up the other one.
We will get the following 3D object, that is a cube:
Therefore, the 4th net makes a cube.
Pls someone help me! Giving brainless
Answer:
ANSWER=5
Step-by-step explanation:
GIVEN=8+(-3)
(+)×(-)=(-)
SO 8-3=5
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14) A positive number is two fifths of another positive number. The sum of the numbers is 49. What arethe two numbers?
Let's use the variable x to represent the second number. The first number is two fifths of x, so the first number is 2x/5.
If the sum of the numbers is 49, we can write the following equation:
[tex]\frac{2}{5}x+x=49[/tex]Now, solving the equation for x, we have:
[tex]\begin{gathered} \frac{2}{5}x+\frac{5}{5}x=49\\ \\ \frac{7}{5}x=49\\ \\ \frac{1}{5}x=7\\ \\ x=7\cdot5\\ \\ x=35 \end{gathered}[/tex]Let's calculate the first number:
[tex]\frac{2}{5}x=\frac{2}{5}\operatorname{\cdot}35=2\cdot7=14[/tex]Therefore the numbers are 14 and 35.
Simplify using the laws of exponents. Use the box to the right of the variable as it’s simplified exponent.
Given:
[tex](15m^8)\placeholder{⬚}^3[/tex]To find:
to simplify using laws of exponents
First, we need to expand the expression:
[tex]\begin{gathered} In\text{ exponent laws, a}^3\text{ = a }\times\text{ a }\times\text{ }a \\ \\ Applying\text{ same rule:} \\ (15m^8)\placeholder{⬚}^3\text{ = \lparen15m}^8)\times(15m^8)\text{ }\times(15m^8) \\ =\text{ 15 }\times\text{ }m^8\times\text{15 }\times\text{ }m^8\times\text{15 }\times\text{ }m^8\text{ } \\ \\ collect\text{ like terms:} \\ =\text{ 15 }\times\text{ 15 }\times15\text{ }\times m^8\times\text{ }m^8\times\text{ }m^8\text{ } \end{gathered}[/tex][tex]\begin{gathered} Simpify: \\ 15\times15\times15\text{ = 3375} \\ \\ m^8\text{ }\times\text{ m}^8\text{ }\times\text{ m}^8 \\ when\text{ multiplying exponents with same base, } \\ \text{we will pick one of the base and add the exponents together } \\ m^8\text{ }\times\text{ m}^8\text{ }\times\text{ m}^8\text{ = m}^{8+8+8} \\ =\text{ m}^{24} \end{gathered}[/tex][tex]\begin{gathered} 15\times15\times15\times m^8\times m^8\times m^8\text{ = 3375 }\times\text{ m}^{24} \\ \\ =\text{ 3375m}^{24} \end{gathered}[/tex]Determine the equation of the graphed circleReminder that the equation should look like the example I provided
The equation of a circle of radius r and center at (h, k) is:
[tex](x-h)^2+(y-k)^2=r^2[/tex]The image provided shows a circle and we must find the radius and center by simple inspection.
The center is located at (-5, 3).
From that point, until I find a point of the circumference I can count 4 units. It is confirmed when I see the segment from (-9, 3) to (-1, 3) as a diameter of length 8. The radius is half the diameter, thus r = 4.
Substituting, we have the required equation:
[tex]\begin{gathered} (x+5)^2+(y-3)^2=4^2 \\ \boxed{\mleft(x+5\mright)^2+\mleft(y-3\mright)^2=16} \end{gathered}[/tex]Maya started to run on a treadmill after setting its timer for 96 minutes. The display says that she has finished 47% of her run. How many minutes have gone by? Round your answer to the nearest tenth.
Answer:
45.1
Step-by-step explanation:
96 x .47 = 45.12
Rounded to the nearest tenth is 45.1
Percent means per hundred [tex]\frac{47}{100}[/tex] to divide by 100 you move the decimal place to places to the left.
what us the area of the triangle if the perimeter is 16
We are asked to find the area of the given triangle.
Recall that the area of a triangle is given by
[tex]A=\frac{1}{2}\cdot b\cdot h[/tex]Where b is the base and h is the height of the triangle.
Let us find the base and height from the given figure.
As you can see,
base = 6
height = 4
[tex]\begin{gathered} A=\frac{1}{2}\cdot b\cdot h \\ A=\frac{1}{2}\cdot6\cdot4 \\ A=\frac{1}{2}\cdot24 \\ A=12 \end{gathered}[/tex]Therefore, the area of the triangle is 12 square units.
Which property is used in the following calculation?
4 (18) (5)
4 (5) (18)
20 (18)
360
A. Identity Property of Multiplication
B. Distributive Property
C. None of these
D. Associative Property of Multiplication
E. Associative Property of Addition
The property which is used in the following calculation is referred to as Associative Property of Multiplication and is denoted as option D.
What is Associative Property of Multiplication?This is referred to as the process in which the the result of the multiplication of three numbers is always the same regardless of the way and manner in which they are arranged.
We were given: 4 (18) (5)
= 4 (5) (18)
= 20 (18)
= 360
The multiplication of the numbers will give the same result of 360 no matter how the numbers are arranged which is why it was chosen as the correct choice.
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Every week a company provides fruit for its office employees. They canchoose from among five kinds of fruit. Which probabilities correctly completethis probability distribution for the 50 pieces of fruit, in the order listed?
Given:
Total number of pieces = 50
So, the probabilities are:
Apples
[tex]P(apples)=\frac{8}{50}=0.16[/tex]Bananas
[tex]P(bananas)=\frac{10}{50}=0.2[/tex]Lemons
[tex]P(lemons)=\frac{5}{50}=0.1[/tex]Oranges
[tex]P(oranges)=\frac{15}{50}=0.3[/tex]Pears
[tex]P(pears)=\frac{12}{50}=0.24[/tex]Answer: A.
The lower quartile for wages at a coffee shop is $8.25, and the upper quartile is $10.75. What can you conclude? a. Half the workers earn between $8.25 and $10.75. b. The median is $9.50. c. The range is $2.50 H COR B
A)Half the workers earn between $8.25 and $10.75.
1) We must remember that the First Quartile responds to 25% of the data points, as well as the Third Quartile responds to 75% of the data points within this dataset.
2) Since the first quartile and the third quartiles were given, then we can tell that
Half the workers earn between $8.25 and $10.75
The median will present exactly what is the value.
Because the difference between the third and the first quartile corresponds to 50%.
Moreover to that, there's not much information about the dataset to figure the range (Highest minus lowest data point) or the median.
An auto mechanic recommends that 3 ounces of isopropyl alcohol be mixed with a tankful of gas (14 gallons ) to increase the octane of the gasoline for better engine performance. At this rate, how many gallons of gas can be treated with a 16-ounce bottle of alcohol (You don’t need to translate or understand just solve the word problem please )
Let be "x" the number of gallons of gas that can be treated with a 16-ounce bottle of alcohol.
According to the information given in the exercise, 3 ounces of isopropyl alcohol should be mixed with 14 gallons of gas.
Then, you can set up the following proportion:
[tex]\frac{14}{3}=\frac{x}{16}[/tex]Now you have to solve for "x":
[tex]\begin{gathered} (16)(\frac{14}{3})=x \\ \\ \frac{224}{3}=x \\ \\ x\approx74.67 \end{gathered}[/tex]Therefore, the answer is:
[tex]\approx74.67\text{ }gallons[/tex]
Lily likes to collect records. Last year she had 12 records in her collection. Now she has 15 records. What is the percent increase of
her collection?
The percent increase of her collection is
Question 1-3
The distance traveled by car, for a duration of time, can be modeled with the equation s= 45t, where s is the distance, in miles, and it is
the time, in hours. Which graph represents this proportional relationship correctly?
120
105
90
Distance (mi)
Distance (mi)
75
60
45
120
30
105
90
15
75
60
45
30
0
15
2
Time (hr)
Time (hr)
100
lon
3
+X
X
120
105
90
Distance (mi)
75
60
45
30
15
0
1
2
Time (hr)
co
X
The equation s = 45t, where s is the distance in miles and it is the time in hours, can be used to simulate the distance driven by a car over a period of time then the car will travel 135 hours in 3 hours.
What is meant by the constant of proportionality?The ratio connecting two given numbers in what is known as a proportional relationship is the constant of proportionality. Constant ratio, constant rate, unit rate, constant of variation, and even rate of change are other names for the constant of proportionality.
Given: The distance traveled by car at a constant rate is proportional to the time spent driving.
In the equation d = 45 t, d denotes the distance (in miles) and t denotes the time (in hours).
d / t = 45 miles per hour
The constant of proportionality = 45 miles per hour.
Also, the distance traveled by car in 1 hour = 45 miles
The distance traveled by car in 3 hours = 3 × 45 = 135 miles
Therefore, a car will travel 135 hours in 3 hours.
The complete question is:
The distance traveled by car at a constant rate is proportional to the time spent driving. In equation d = 45t, d represents the distance (in miles) and t represents the time (in hours).
A. What is the constant of proportionality? _____ miles per hour
B. How far will the car travel in 3 hours? _______ miles
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URGENT!! ILL GIVE
BRAINLIEST!!!!! AND 100 POINTS!!!!!
Order the numbers from least to greatest
Answer:
-1, √4/5, -6/5, √3, 2, -3√9, 2√125
Step-by-step explanation:
Writing the equation of a circle centered at the origin given it’s radius or appoint on the circle
The equation of the circle has the following form:
[tex](x-h)^2+(y-k)^2=r^2[/tex]Where
(h,k) are the coordinates of the center of the circle
r is the radius of the circle
If the center of the circle is at the origin, (0,0) and it passes through the point (0,-9), since both x-coordinates are equal, the length of the radius is equal to the difference between the y-coordinates of the center and the given point:
[tex]r=y_{\text{center}}-y_{point=}0-(-9)=0+9=9[/tex]The radius is 9 units long.
Replace the coordinates of the center and the length of the radius in the formula:
[tex]\begin{gathered} (x-0)^2+(y-0)^2=9^2 \\ x^2+y^2=81 \end{gathered}[/tex]So, the equation of the circle that has a center in the origin and passes through the point (0.-9) is:
[tex]x^2+y^2=81[/tex]