Problem 7: Correct
Problem 8: Correct
Problem 9: Correct
The steps are below if you are curious
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Problem 7
S = 180*(n-2)
2340 = 180*(n-2)
2340/180 = n-2
13 = n-2
n-2 = 13
n = 13+2
n = 15
I'm using n in place of lowercase s, but the idea is the same. If anything, it is better to use n for the number of sides since S already stands for the sum of the interior angles. I'm not sure why your teacher decided to swap things like that.
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Problem 8
First find y
y+116 = 180
y+116-116 = 180-116
y = 64
which is then used to find x. The quadrilateral angles add up to 180*(n-2) = 180*(4-2) = 360 degrees
Add up the 4 angles, set the sum equal to 360, solve for x
x+y+125+72 = 360
x+64+125+72 = 360 ... substitution (plug in y = 64)
x+261 = 360
x+261-261 = 360-261
x = 99
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Problem 9
With any polygon, the sum of the exterior angles is always 360 degrees
The first two exterior angles add to 264. The missing exterior angle is x
x+264 = 360
x+264-264 = 360-264
x = 96
Answer:
Vertical stretch of factor of 3
translated to the right 2
translated up 5
Step-by-step explanation:
Given:
Jake bought 3 drawing pens for $8.07.
Each pen costs the same amount.
To find:
How much did he spend for one pen?
Solution:
Let x be the cost of each pen. Then
Cost of three pens = 3x
Jake bought 3 drawing pens for $8.07.

Divide both sides by 3.


Therefore, he spend $2.69 for one pen.
You can model this with the equation 4x+3=15 since it is a number (x) times 4 with 3 added and equals 15.
Subtract 3 from both sides
4x=12
Divide both sides by 4
x=3
Answer:
so, lauren isn't correct
Step-by-step explanation:
3x + 4 (2x + 5) = 6x + 5x + 5
3x + 8x + 20 = 11x + 5
11x + 20 ≠ 11x + 5