Answer:
Junior PSAT
Training Packet
2016-17
Math Department
Answer Key
Section 3: Math Test — No Calculator
QUESTION 1.
Choice C is correct. Subtracting 6 from each side of 5x + 6 = 10 yields 5x = 4.
Dividing both sides of 5x = 4 by 5 yields x =
_4
5
. Te value of x can now be
substituted into the expression 10x + 3, giving 10 ( _4
5 ) + 3 = 11.
Alternatively, the expression 10x + 3 can be rewritten as 2(5x + 6) − 9, and
10 can be substituted for 5x + 6, giving 2(10) − 9 = 11.
Choices A, B, and D are incorrect. Each of these choices leads to 5x + 6 ≠ 10,
contradicting the given equation, 5x + 6 = 10. For example, choice A is
incorrect because if the value of 10x + 3 were 4, then it would follow that
x = 0.1, and the value of 5x + 6 would be 6.5, not 10.
QUESTION 2.
Choice B is correct. Multiplying each side of x + y = 0 by 2 gives 2x + 2y = 0.
Ten, adding the corresponding sides of 2x + 2y = 0 and 3x − 2y = 10 gives
5x = 10. Dividing each side of 5x = 10 by 5 gives x = 2. Finally, substituting
2 for x in x + y = 0 gives 2 + y = 0, or y = −2. Terefore, the solution to the
given system of equations is (2, −2).
Alternatively, the equation x + y = 0 can be rewritten as x = −y, and substituting x for −y in 3x − 2y = 10 gives 5x = 10, or x = 2. Te value of y can then
be found in the same way as before.
Choices A, C, and D are incorrect because when the given values of x and
y are substituted into x + y = 0 and 3x − 2y = 10, either one or both of the
equations are not true. Tese answers may result from sign errors or other
computational errors.
QUESTION 3.
Choice A is correct. Te price of the job, in dollars, is calculated using
the expression 60 + 12nh, where 60 is a fxed price and 12nh depends on the
number of landscapers, n, working the job and the number of hours, h, the job
takes those n landscapers. Since nh is the total number of hours of work done
when n landscapers work h hours, the cost of the job increases by $12 for each
hour a landscaper works. Terefore, of the choices given, the best interpretation
of the number 12 is that the company charges $12 per hour for each landscaper.
Choice B is incorrect because the number of landscapers that will work each
job is represented by n in the equation, not by the number 12. Choice C is
incorrect because the price of the job increases by 12n dollars each hour,
which will not be equal to 12 dollars unless n = 1. Choice D is incorrect
because the total number of hours each landscaper works is equal to h. Te
number of hours each landscaper works in a day is not provided.
QUESTION 4.
Choice A is correct. If a polynomial expression is in the form (x)2
+ 2(x)(y) +
(y)2
, then it is equivalent to (x + y)2
. Because 9a4
+ 12a2
b2
+ 4b4
= (3a2
)2
+
2(3a2
)(2b2
) + (2b2
)2
, it can be rewritten as (3a2
+ 2b2
)2
.
Choice B is incorrect. Te expression (3a + 2b)4
is equivalent to the product
(3a + 2b)(3a + 2b)(3a + 2b)(3a + 2b). Tis product will contain the term
4(3a)3
(2b) = 216a3
b. However, the given polynomial, 9a4
+ 12a2
b2
+ 4b4
,
does not contain the term 216a3
b. Terefore, 9a4
+ 12a2
b2
+ 4b4 ≠ (3a + 2b)4
.
Choice C is incorrect. Te expression (9a2
+ 4b2
)2
is equivalent to the
product (9a2
+ 4b2
)(9a2
+ 4b2
). Tis product will contain the term (9a2
)
(9a2
Answer:
that looks hard
Step-by-step explanation:
b
Match the correct scenario with the correct unit rate format.
1. meters/second
2. $/pound
3. $/ tire
4. people/class
5. miles/gallons
6. calories/serving
What is the value of the expression 5(X+3) when X=-3?
Answer:
0
Step-by-step explanation:
5(x+3) replace x with -3
5(-3+3)
5(0)
0
What is the quotient of -32/8?
Answer:
Hope it help you
Stayhomestaysafe
Plz mark my answer brainliest✍️✍️
Step-by-step explanation:
[tex] - 32 \div8 = - 4[/tex]Answer is -4
REAL NAME - SHRESTH DUBEY
-4 is the Answer.
-32/8 would be -4
A football team scored a total of 41 points in a Sunday game. They scored 7 points in the first quarter, 10 points in the second quarter, and 7 points in the third quarter. How many points did the team score in the fourth quarter?
41 - 7 - 10 - 7 = 41 - 24 = 17.
The team scored 17 points in the last quarter.
3xsquared +13x-10
HELPP PLEASE
Answer:
(x + 5)(3x - 2)
Step-by-step explanation:
Assuming you require the expression factorised.
3x² + 13x - 10
Consider the factors of the product of the x² term and the constant term which sum to give the coefficient of the x- term.
product = 3 × - 10 = - 30 and sum = + 13
The factors are + 15 and - 2
Use these factors to split the x- term
3x² + 15x - 2x - 10 ( factor the first/second and third/fourth terms )
= 3x(x + 5) - 2(x + 5) ← factor out (x + 5) from each term
= (x + 5)(3x - 2) ← in factored form
Which of the following statements correctly justifies the steps in the solution below?
Given
Step 1
Step 2
Step 3
Step 4
6(3x - 4) - 26 = 40
18x - 24 - 26 = 40
18x - 50 = 40
18x = 90
x = 5
O The Associative Property is used to create Step 1.
O The Distributive Property is used to create Step 3.
o The Division Property is used to create Step 4
o The Subtraction Property is used to create Step 2.
Answer:
The Division Property is used to create Step 4
Answer:b
Step-by-step explanation:
writing equations of lines
Step-by-step explanation:
Equation of straight line is y=mx+c
choose any two points on straight line
for me I choose:(-3,11) and (3,-1)
use these two points to find gradient,m.
m= (-1-11)/(3-(-3))
m= -2
now, y=-2x+c
choose any point on the straight line
I choose point (3,-1)
sub the point into the equation to find c
-1=-2(3)+c
c=5
equation: y=-2x+5
A line has a slope of
1/4
and passes through the point (0.2,
4/5
Find the value of b, the y-intercept.
b = ???
Answer:
b = 3/4
Step-by-step explanation:
Using point slope: y - y1 = m(x - x1).
Substitute your given slope, given point, and subsitute 0 in for x and solve for y since the y intercept is the y value when x = 0.
0.2 = 1/5, so 1/5 * 1/4 = 1/20
Therefore: y - 4/5 = 1/4(0 - 0.2) → y - 4/5 = -1/20 → y = 4/5 - 1/20 → 15/20 → 3/4
b = 3/4
Using point slope: y - y1 = m(x - x1).
Substitute your given slope, given point, and subsitute 0 in for x and solve for y since the y intercept is the y value when x = 0.
0.2 = 1/5, so 1/5 * 1/4 = 1/20
Therefore: y - 4/5 = 1/4(0 - 0.2) → y - 4/5 = -1/20 → y = 4/5 - 1/20 → 15/20 → 3/4
PLEASE HELP!!!!! Sometimes two transformations, one performed after the other, have a nice description as a single transformation. For example, instead of translating 2 units up followed by translating 3 units up, we could simply translate 5 units up. Instead of rotating 20 degrees counterclockwise around the origin followed by rotating 80 degrees clockwise around the origin, we could simply rotate 60 degrees clockwise around the origin. Can you find a simple description of reflecting across the x-axis followed by reflecting across the y-axis?
Answer: A rotation of 180° around the origin.
Step-by-step explanation:
When we have a point (x, y) and we want to reflect it over a given line, the distance between the point and the line remains invariant under the transformation.
This is equivalent as a rotation around a point, the "radius" of the circle that we are creating when we do a rotation is constant.
Now, let's analyze our case:
First a reflection over x-axis, and then a reflection over the y-axis.
This means that if our point starts in quadrant 1 then:
-The reflection over the x-axis will leave our point in quadrant 4.
-The reflection over the y-axis will leave our point in quadrant 3.
Now, if our point stated on quadrant 2.
-The reflection over the x-axis will leave our point in quadrant 3.
-The reflection over the y-axis will leave our point in quadrant 4.
So essentially, these transformations "move" our point to the opposite quadrant, such that the rules of the reflection are applied.
This means that:
The distance between our point and the x-axis does not change.
The distance between our point and the y-axis does not change.
But if the distances to both axes do not change, then the distance between our point and the origin also does not change.
This means that we can find a rotation that is equivalent to this transformation.
So we must look at a rotation that moves our point 2 quadrants.
a rotation that moves our point 2 quadrants will be:
A rotation of 180° around the origin.
Please help me with this.
Answer:
y = (-1/2)x + 4
Step-by-step explanation:
Slope (m): (-1/2)
down one, right two
y-intercept (b): 4
y = mx + b
The slope-intercept equation if the line is [tex]y=-\frac{1}{2}x+4[/tex]
To find the slope, you must put the 2 points into the slope equation.
[tex]\frac{3-4}{2-0}=\frac{-1}{2}[/tex]
And to find the y-intercept, you must find where the line crosses the y-axis.
(0,4)
Suzy's Sculpting gym charges a $10 application fee and $12 per month for membership. Tami's Toning does not charge an application fee, but charges $14 per month for membership. After how many months will the total cost of membership be the same for both gyms?
Answer:
Total cost of membership will be the same for both gyms after 5 months.
Step-by-step explanation:
Given: Suzy's Sculpting gym charges a $10 application fee and $12 per month for membership.
Tami's Toning does not charge an application fee, but charges $14 per month for membership.
To find: After how many months will the total cost of membership be the same for both gyms
Solution:
Let [tex]t[/tex] denotes number of months after which total cost of membership will be the same for both gyms
For Suzy's Sculpting gym,
Total charges [tex]= 10+12t[/tex]
For Tami's Toning,
Total charges [tex]=14t[/tex]
Now solve [tex]10+12t=14t[/tex]
[tex]10+12t=14t\\10=14t-12t\\10=2t\\t=\frac{10}{2}\\ t=5[/tex]
So, total cost of membership will be the same for both gyms after 5 months.
HELP!!!!!!!!!!!!!!!!!!
Answer:
it is an acute angle
Step-by-step explanation:
less then 90° is a acute and above 90° angle is an obtuse
find the value of x that makes the lines parallel 3x-9 2x-1
Answer:
x=8
Step-by-step explanation:
set the equations equal to themselves and solve
3x-9=2x-1
+9 and -2x
x=8
Check:
3(8)-9=2(8)-1
24-9=16-1
15=15
Question 2 (1 point)
Explain how you used the distribute property to find an equivalent expression for
4 (3+x)
ANYONE ITS WORTH 10 POINTS PLEASE???
Help me ASAP major grade
Answer:
$5.58
Step-by-step explanation:
Because divide 12 by 67:
67 ÷ 12 = 5.58
5.58 is the answer
Hope this helped! Pls Brainliest!
Answer:
$5.58
Step-by-step explanation:
$67.00÷12=$5.58
Hope this helps!
Tim dug a hole that was 16 1/2 inches deep. He left a pile of dirt next to the at was inches high. Show how you could use subtraction to find the e from the top of the pile of dirt to the bottom of the hole. 8 3/4 Tim dug a hole that hole that was distance from the
Answer: 2 inches
Step-by-step explanation:
14 inches
Step-by-step explanation:
Length of the hole = 16(½) inches
Length of the dirt = 8(¾)inches
The distance between the top of the pile to the bottom of the hole = ?
Since the dirt is beside the hole and not inside the hole, we can find it's length using addition.
Distance from the top to the bottom = length of dirt + length of the hole
Length of dirt = 8×¾ = 6 inches
Length of the hole = 16 × ½ = 8 inches
Distance from the top of the dirt to the bottom of the hole = (6 + 8) inches
Distance from the top of the dirt to the bottom of the hole = 14 inches
Note: the only way we can use subtraction here is if the hole was filled with dirt, what's the distance that's left
Distance left = length of hole - length of dirt
Distance left = 8 - 6 = 2 inches .
Find an ordered pair (x, y) that is a solution to the equation.
5x + y=9
Answer:
Some points are: (1, 4), (0, 9), and (3, -6), just to name a few.
Step-by-step explanation:
We can find out an ordered pair for this equation by plotting the line 5x + y = 9 on a graph. If you graph 5x + y = 9, then we see that the point (1, 4) is a point that the line intersects. Let's substitute that values:
5(1) + 4 = 9
Order of operations, multiply first...
5(1) = 5
Then it becomes...
5 + 4 = 9
We can see that 5 plus 4 actually does equal 9, so the point (1, 4) works. Let's try a different point. We can see the point (0, 9) is another point that the line intersects. Same process for this point too.
5(0) + 9 = 9
Then...
5(0) = 0
0 + 9 = 9
We see that 0 plus 9 ALSO works, but let's try one more time. Another point that works is the point (3, -6) Again, same process.
5(3) + -6 = 9
That is equal to:
5(3) - 6 = 9
Simplify...
5(3) = 15
15 - 6 = 9
15 minus 6 works as well! Any point that the line intersects will be a solution for the equation. I hope this helps!
PLEASE HELP FAST!! WILL MARK AS BRAINLIEST IF GIVEN GOOD ANSWER
Answer:
80 degrees
Step-by-step explanation:
both intersections are the same, so we can count them as one. We notice that one line is a straight line compared to other so we can subtract 100 from 180 and get 80
Answer:
80
Step-by-step explanation:
Vertical angles equal 360 in total and the angles across from each other equal the same. 100 x 2 = 200
360-200 = 160
160/2 = 80
I hope this helps enjoy your day!
ayudaaaaaaaaaaaaaaaaa
Construct a line through R that is perpendicular to the line
Answer: just did it 3 secs. ago
Step-by-step explanation:
The answer is shown below.
Perpendicular:In simple geometry, two geometric objects cross at a right angle ( [tex]90^{0}[/tex]degrees or [tex]\frac{\pi }{2}[/tex] radians ) if they are perpendicular to one another.If two lines cross at a right angle, they are said to be perpendicular to one another. A first line is explicitly said to be perpendicular to a second line if the two lines meet and the straight angle on one side of the first line is cut by the second line into two congruent angles at the point of junction.Therefore, the Construction of a line through R that is perpendicular to the line is shown below:
Know more about perpendicular lines here:
https://brainly.com/question/1202004
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There are 90 people in a group.
A sixth of the people in the group are men.
The number of women in the group is 2 times the number of men in the group
The rest of the people in the group are children.
the number of children in the group : the number of men in the group = n: 1
Work out the value of n.
You must show how you get your answer.
Answer:
n=3
Step-by-step explanation:
90×1/6=15 men
15*2=30 women
90-15-30=45 children
45 children: 15 men
3:1 ratio of children to men
n=3
A toy store is having a sale. A video game system has an original price of $99. It is on sale for 40% off the original price. Find the sale price of the game system. Round to the nearest cent.
Answer:
The price would now be $59.40
Step-by-step explanation:
$59.4 is the sale price of the game system.
What is selling price?
The selling price is how much a buyer pays for a product or service.
Given,
A toy store is having a sale. A video game system has an original price of $99.
It is on sale for 40% off the original price.
We need to find how much 40% of $99.
40/100×99=0.4×99=39.6.
So sale price of the game system is $99-$39.6=$59.4.
Therefore sale price of the game system is $59.4.
To learn more on Selling price click:
https://brainly.com/question/27796445
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HELP PLS HOW DO U DO THIS
Answer:
10
Step-by-step explanation:
1/3 of 24 is 8, and 1/4 is 6. 8+6=14, and 24-14=10. So I think that 10 people brought chips.
Answer:
10
Step-by-step explanation:
24 ÷ 3 = 8 so one third is 8
24 ÷ 4 = 6 so one fourth is 6
8 + 6 = 14 (14 people brought drinks or dessert)
24 - 14 = 10
ten people brought chips.
What is the measure
of ZA, in degrees?
20
At the carnival the ratio of rides to games was 9:8. For every ___games there are ___rides.
A.8 games, 17 rides
B.8 games, 9 rides
C.9 games, 17 rides
D.9 games, 8 rides
Answer:
The answer is B.8 games,9 rides
Coming in at lunch for extra math help has really paid off! You started out scoring
18 points on each quiz, but your number of points has been increasing 36% per
month for the last 5 months. How many points are you now earning per quiz?
Answer:
83 points.
Step-by-step explanation:
Solve for a: u = 3b - 2a + 2
If a=2 then you would have u=3b-2(2) or u=3b-4 :)
Answer:
Step-by-step explanation:
B= 2/3a-2//3+1/3u, u equals R, A equals r
A=3/2b+1-1/2u, u equals R b equals R
Which relationships have the same constant of proportionality between yyy and xxx as the equation y=\dfrac{1}{2}xy= 2 1 xy, equals, start fraction, 1, divided by, 2, end fraction, x? Choose 3 answers: Choose 3 answers:
Answer:
A & B
Step-by-step explanation:
See attachment for complete question
Given
[tex]y = \frac{1}{2}x[/tex]
Analyzing the given options
Option A:
[tex]6y = 3x[/tex]
Divide both sides by 6
[tex]\frac{6y}{6} = \frac{3x}{6}[/tex]
[tex]y = \frac{3x}{6}[/tex]
[tex]y = \frac{1}{2}x[/tex]
This is true for the given expression:
Option B:
From the graph:
x = 2, when y = 1
x = 4, when y = 2
Solving for the slope:
[tex]m = \frac{y_2 - y_1}{x_2 - x_1}[/tex]
[tex]m = \frac{2 -1}{4 - 2}[/tex]
[tex]m = \frac{1}{2}[/tex]
The equation is then calculated as:
[tex]y - y_1 = m(x - x_1)[/tex]
[tex]y - 1 = \frac{1}{2}(x - 2)[/tex]
[tex]y - 1 = \frac{1}{2}x - 1[/tex]
Add 1 to both sides
[tex]y - 1 +1 = \frac{1}{2}x - 1 + 1[/tex]
[tex]y = \frac{1}{2}x[/tex]
This is also true for the given expression.
Option C:
From the graph:
x = 2, when y = 4
x = 4, when y = 8
Solving for the slope:
[tex]m = \frac{y_2 - y_1}{x_2 - x_1}[/tex]
[tex]m = \frac{8 - 4}{4 - 2}[/tex]
[tex]m = \frac{4}{2}[/tex]
[tex]m =2[/tex]
The equation is then calculated as:
[tex]y - y_1 = m(x - x_1)[/tex]
[tex]y - 4 = 2(x - 2)[/tex]
[tex]y - 4 = 2x - 4[/tex]
Add 4 to both sides
[tex]y - 4 + 4= 2x - 4 + 4[/tex]
[tex]y = 2x[/tex]
This isn't true for the given expression.
Option (D):
From the table:
x = 2, when y = 1
x = 4 when y = 3
Solving for the slope:
[tex]m = \frac{y_2 - y_1}{x_2 - x_1}[/tex]
[tex]m = \frac{3 - 1}{4 - 2}[/tex]
[tex]m = \frac{2}{2}[/tex]
[tex]m = 1[/tex]
The equation is then calculated as:
[tex]y - y_1 = m(x - x_1)[/tex]
[tex]y - 1 = 1 * (x - 2)[/tex]
[tex]y - 1 = x - 2[/tex]
[tex]y = x - 2 +1[/tex]
[tex]y = x - 1[/tex]
This isn't true for the given expression.
Answer:
A,B, and E
Step-by-step explanation:
trust me.
Non example of complex fraction.
Answer:
42/6
Step-by-step explanation:
:P
Maya is the manager for the track team. She created a table to compare finish times from the second practice to the first practice.
100 m Dash Finish Time Comparison
Runner
Second practice time compared to first practice time
Joshua
+1.03
Kedwin
–0.97
Leila
–0.95
Miguel
+1.1
Nicole
–0.87
Maya claims that the runners’ order of most improved to least improved is Miguel, Joshua, Nicole, Leila, and Kedwin. Which statement describes whether Maya is correct?
Maya is correct because she compared each digit in the same place value. Miguel added the most time to his sprint so he is most improved.
Maya is incorrect because –0.87 < –0.95 < –0.97. Runners that decrease times are improving, and those that add time are not improving.
Maya is incorrect because 1.1 < 1.03. She should switch the order of Joshua and Miguel because Joshua added more time to his run.
Maya is incorrect because she listed the runners from least improved to most improved. Runners that decreased times are improving, and those that add time are not improving.
Answer:
d
Step-by-step explanation:
Answer:
D
Step-by-step explanation:
its D i took test 2020 edge