x^2-x-2=0 as a complete square
Answer:
[tex]x_1=2; x_2=-1[/tex]
Step-by-step explanation:
The square term is [tex]x^2[/tex] so we expect the complete square to be of the form [tex](x-a) ^2=x^2+2ax+a^2[/tex].
Let's compare the first degree terms now: we have [tex]2ax[/tex] on one side and [tex]-1x[/tex] on the other. That would make [tex]a=- \frac12[/tex]. At this point we have still the second squared term, so we add and subtract [tex]\frac14 = (\frac12)^2[/tex]
Our equation becomes:
[tex]x^2-x+\frac14 -\frac14-2 =0\\(x-\frac12)^2-\frac94=0[/tex]
(the [tex]\frac94[/tex] term comes from rewriting [tex]2= \frac84[/tex] and adding the terms out of the bracket).
At this point it's just solving the equation:
[tex](x-\frac12)^2 = \frac94 \rightarrow x-\frac12=\pm\frac32\\x=\frac12\pm\frac32\\x_1=\frac42 = 2; x_2=\fra-\frac22=-1[/tex]
If a coin is flipped 5 times and heads comes up 2 times, what is the relative frequency of heads coming up?
Answer:
0.40 is your answer
Step-by-step explanation:
0 .40 is your answer
Find the length of the third side. If necessary, round to the nearest tenth. 12 18
Answer (assuming that the shape is a right triangle):
If looking for the hypotenuse: 21.63
If looking for one leg, given other leg is 12, and the hypotenuse is 18: 13.42
Step-by-step explanation:
Given the length of two sides of a right triangle, we can use the pythagorean theorem to find the length of the third side. The pythagorean theorem is [tex]a^{2} + b^{2} = c^{2}[/tex] or [tex]c=\sqrt{(a^{2} + b^{2})}[/tex]. Given this question, I do not know what side of the triangle the problem is looking for, I would assume the hypotenuse, so let's do that first.
[tex]c = \sqrt{(12^{2} +18^{2})} \\c = \sqrt{468} \\c = 21.63[/tex]
Or we can manipulate the equation to find different scenarios of possible legs. Such equation that can be used is [tex]a = \sqrt{c^2 - b^2}[/tex], where c is the hypotenuse.
Only one scenario is possible, with the hypotenuse being 18 because the hypotenuse cannot be less than one of the legs, or that leg basically becomes the hypotenuse because such side is the largest (12 < 18).
So our last scenario is, if we are looking for one leg, given other leg is 12, and the hypotenuse is 18.
[tex]a = \sqrt{18^2-12^2} \\a = \sqrt{180} \\a = 13.42[/tex]
These are our possible answers.
Under his cell phone plan, Justin pays a flat cost of $56 per month and $5 per gigabyte. He wants to keep his bill under $65 per month. Write and solve an inequality which can be used to determine xx, the number of gigabytes Justin can use while staying within his budget
Answer:
56 + 5xx < 65
xx < 1.8
Step-by-step explanation:
56 + 5xx < 65
subtract 56 on both sides
56 + 5xx < 65
-56 -56
5xx < 9
divide by 5 on both sides
5xx/5 < 9/5
xx < 1.8 gigabytes
Can you please help me quickly!!
Answer:
to struggle to succeed when chances are bad
Step-by-step explanation:
She got nervous and froze when she thought she was going to lose.
Solve the system of equations below. Thankyou!
Answer:
x = - 9
y = 5
Step-by-step explanation:
EQ1 + EQ2
Substitute the value of X in either EQ1 or EQ2
The values in the table below represent function B, which is linear function (-3,-7) (-1,-1) (1,5) (3,11)
Answer:
I don't see the picture of the problem
I CANT FIGURE THIS OUT I NEED HELP
Solve and graph the inequality:
[tex]-1/2x + 8\geq 6[/tex]
Answer:
[tex]x\leq 4[/tex]
Step-by-step explanation:
Given:
[tex]-\frac{1}{2}x+8\ge 6[/tex]
Solve:
[tex]\mathrm{Subtract\:}8\mathrm{\:from\:both\:sides}[/tex]
[tex]-\frac{1}{2}x+8-8\ge \:6-8[/tex]
[tex]\mathrm{Simplify}[/tex]
[tex]-\frac{1}{2}x\ge \:-2[/tex]
[tex]Multiply\:both\:sides\:by\:-1[/tex]
[tex]\left(-\frac{1}{2}x\right)\left(-1\right)\le \left(-2\right)\left(-1\right)[/tex]
[tex]\mathrm{Simplify}[/tex]
[tex]\frac{1}{2}x\le \:2[/tex]
[tex]\mathrm{Multiply\:both\:sides\:by\:}2[/tex]
[tex]2\cdot \frac{1}{2}x\le \:2\cdot \:2[/tex]
[tex]\mathrm{Simplify}[/tex]
[tex]x\leq 4[/tex]
[tex]\mathrm{Therefore,}[/tex]
[tex]\begin{bmatrix}\mathrm{Solution:}\:&\:x\le \:4\:\\ \:\mathrm{Interval\:Notation:}&\:(-\infty \:,\:4]\end{bmatrix}[/tex]
~lenvy~
PLEASEEE HELP LOOK AT PICTURE!!!
Answer:
a 64/3
Step-by-step explanation:
4^3 * 1/3 = 64/3
7
The number of chocolates, C. needed for a party is worked out using
the formula C = 6n, where n is the number of people attending,
How many chocolates are needed if there are:
b) 12 people?
a) 8 people?
C) 40 people?
d) 50 people?
Answer: (b) 72 (A) 48 (c) 240 (D) 300
Step-by-step explanation:I just multiplied
Answer:
6*12=72
6*8=48
6*40=240
6*50=200
Step-by-step explanation:
just substitute the given number for n and mulitply
The function f(x)=4x^(5)-2x^(3)+8x is:
Answer:
C. Odd
Step-by-step explanation:
If you reflect this function across the y-axis it is not symmetrical, therefore it is not an even function
But, if you rotate this function by 180 degrees, it is unchanged, therefore it is and odd function
What quadrilateral always has 4 congruent angles and opposite sides that are congruent and parallel? Please answer it correctly.
Answer:
Square
Step-by-step explanation:
Requirements that make a square, a square;
Four sidesCongruent angles (all 90°)Opposite sides are congruent/the same.Opposite sides are also parallel because the lines of a square do not intersect.Answer:
Square
Explanation:
A square has four congruent angles as each angle measure is 90°. A square can never have an angle other than 90°. A square also has all four equal sides, and its opposite side lengths are parallel because all angles of a square must be 90°.
Please look at attached image for reference.
In this figure, ∠1 and ∠2 are located on a line.
Let m∠1=x° and m∠2=(45x)°.
What is the value of x?
Enter your answer in the box.
Answer:
Your answer would be 100
Step-by-step explanation:
4/5 of 100 is 80, 100 and 80 add up to 180, which makes it a supplementary angle, we know it is a supplementary angle because the figure has a line, so x = 100
Nil and Ethan are brothers. They left their home at the same time and drove to the same beach. Nil drove at a speed of 30 miles per hour. Ethan drove at a speed of 20 miles per hour. Nil arrived at the beach 0.5 hour earlier than Ethan. What is the distance between their home and the beach?
Answer:
10 miles
Step-by-step explanation:
Ethan drove at a speed of 20 miles per hour. Nil arrived at the beach 0.5 hour earlier than Ethan. What is the distance between their home and the beach? Every hour, Nil gets ahead of Ethan 30 - 20 = 10 miles.
You find a ring at a garage sale and purchase it for $2. Explain how you could use a simple balance and graduated cylinder to determine if it is made of gold or if it’s a fake.
Density of water is 1000kg/m^3
Gold should sink downIf yes then it's pure goldCan someone help me with this
Answer:
NO, but I know who can
Step-by-step explanation:
A manager drew this box-and-whisker plot to represent the number of minutes each of the company's 360 employees took on their break.
How many employees took a break that lasted between 37 and 41 minutes?
Select from the drop-down menu to correctly complete the statement.
Given the box-and-whisker plot, the number of employees that took a break that lasted between 37 - 41 minutes is: 180.
What is a Box-and-whisker Plot?A box-and-whisker plot is a graphical representation of a data set showing how the data set is distributed into percentiles such as 25%, 50%, and 75%.
The range of the rectangular box covers 50% of the data set.
Thus, 37 - 41 minutes lies between 50% on the box-and-whisker plot, therefore:
50/100 × 360 = 180 employees.
In summary, given the box-and-whisker plot, the number of employees that took a break that lasted between 37 - 41 minutes is: 180.
Learn more about box-and-whisker plot on:
https://brainly.com/question/3473797
Answer:
The answer is 90
Step-by-step explanation:
Its not 180 I take k12 also.
Mya is redecorating her bedroom. The room is in the shape of right rectangular prism. The dimensions of the room are: 12 feet in length by 14 feet in width by 8 feet in height. She plans to cover the floor with tile. The cost of the tile is $4 per square foot. She plans to cover the walls and the ceiling with paint. Each container of paint costs $16 and can cover 146 ft². What is the total cost of the tile flooring and paint needed for this room? Drag and drop the responses to correctly complete these sentences.
Answer:i took the test and this was my answer. goodluck mate :)
Step-by-step explanation:
Below are two parallel lines with a third line intersecting them.
(Please help T-T)
Answer:
x = 136
Step-by-step explanation:
44 + x = 180
x = 180 - 44
x = 136
Type the correct answer in the box. Use numerals instead of words. If necessary, use / for the fraction bar.
In the equation n+5 - n- 10 = 1the value of n is
Answer:
No Solution
Step-by-step explanation:
If you grouped like terms, you would get [tex]n+(-n)+5-10=1[/tex]
Both n's would cancel each other out.
I hope this helps! (If it's wrong, then tell me, I'll try to find the correct answer...)
Select the correct answer.
which function is continuous across its domain?
Answer:
B
Step-by-step explanation:
This year Heather watched 20 movies. She thought that 9 of them were very good. Of the movies she watched, what percentage did she rate as very good?
Answer:
45%
Step-by-step explanation:
PLEASE MARK ME AS BRAINLIEST I REALLY WANT TO LEVEL UP
HAPPY BIRTHDAY!
You have decided to give your best friend a bag of red
and green marbles for his birthday. Your friend likes
green marbles better than red ones, so the bag has
twice as many green marbles as red. The label on the
bag says it contains a total of 84 marbles.
How many green marbles are in the bag? Write a
system of equations for this problem. Then solve the
problem using any method you like. Be sure to check
your solution
Answer:
56
Step-by-step explanation:
(84÷3) · 2 = x
28 · 2 = 56
Hope that helps!
THIS IS EXPONENTIAL FROM TWO POINTS
If f(x) is an exponential function where f(3.5)=21 and f(6.5)=69, then find the value of f(9), to the nearest hundredth.
Answer:
i think the answer is 144
Step-by-step explanation:
ohhh so first we should try finding the slope here. since we know the points are (3.5 , 21) and (6.5, 69) we can use the formula to look for the slope
the formula is:
y2 - y1 / x2 - x1
lets substitute
69 - 21 / 6.5 - 3.5
48 / 3
16
f(x) = 16x + b
now we just substitute
btw i dont think we need to find b because this inst a linear equation? im not sure but yea i dont think we need to find the y-intercept
so anyways
f(9) = 16(9)
= 144
Solve 58 - 10x< 20 + 9x.
-
O A. x2
O B. Xs2
O c. xs-2
O D. x2-2
I am not sure what you are asking by the options provided as the formatting has been messed up, but if you simplify the given equation you end up with:
x > 2
Step-by-step explanation:
Given
58 - 10x< 20 + 9x
Add 10x to both sides of the equatoin
58 < 20 + 19x
Subtract 20 from both sides of the equatoin
38 < 19x
2 < x
x > 2
whats the value of x+26
Answer:x = 154°
Step-by-step explanation:
The central angle and the angle between the tangents are supplementary, so
x + 26° = 180° ( subtract 26° from both sides )
x = 154°
Answer: 154 degrees
Step-by-step explanation: subtract 180 from 26 To get it .
f(x) = 3x - 2x - 5
Factoring quadratics
Answer:
[tex](3x -5)(x+1)[/tex]
Step-by-step explanation:
Factoring [tex]3x^{2} -2x-5=0[/tex] results in [tex](3x -5)(x+1)[/tex]
White gold is made from gold, palladium, nickel and zinc in the ratio 15:2:2:1. A white gold ring contains 9g of gold. What is the mass of the ring?
Answer:
The mass of the ring is 12 grams.
Step-by-step explanation:
Total 20 parts
Gold 3/4 total mass (15/20)
3/4=9g
1/4=3g
4/4=12g
Answer:
mass of the ring = 12 g
Step-by-step explanation:
Given ratio
gold : palladium : nickel : zinc = 15 : 2 : 2 : 1
Add the ratios: 15 + 2 + 2 + 1 = 20
Therefore, as a fraction, gold is [tex]\sf \dfrac{15}{20}=\dfrac34[/tex] of the total mass of the ring.
Let the mass of the ring = x
As the ring containts 9 g of gold
[tex]\sf \implies \dfrac34x=9[/tex]
[tex]\sf \implies x=9 \cdot \dfrac43[/tex]
[tex]\sf \implies x=12[/tex]
Therefore, the mass of the ring is 12 g
comprising 9 g of gold, 1.2 g of palladium, 1.2 g of nickel and 0.6 g of zinc.
A small bag of chips contains 0.3 of a cup of sugar. if a large bag of chips is the same as 6.4 small bags, how much sugar does a large bag contain?
The sixth-grade art students are making a mosaic using tiles in the shape of right triangles. each tile has leg measures of 5 cm and 6 cm. if there are
150 tiles in the mosaic, what is the area of the mosaic?
a 10 cm2
b 2250 cm 2
c 165 cm2
d 4500 cm2
Answer:
Below in bold.
Step-by-step explanation:
The area of each triangle = 1/2 * height * base
As it is a right triangle the height is equal to one of its sides, so
Area of 1 triangle = 1/2 * 6 * 5
= 15 cm^2
Area of mosaic = 150 * 15
= 2250cm^2.