-7c+9=c+1 (subtract c on both sides)
-8c+9=1 (subtract 9 on both sides)
-8c=-8 (divide by -8 on both sides to get c by its self)
c=1
your answer is 1.
Answer:

Step-by-step explanation:

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:
3 shirts, 6 shorts
Step-by-step explanation:
A total of $264 is spent during shopping on shirts and shorts
Each shirt costs $24
Each shorts cost $32
Therefore the quantity of shirts and shorts bought can be calculated as follows
24× 3= 72
32×6= 192
192+72= 264
Hence 3 shirts and 6 shorts were bought
Answer:
(2,-5)
Step-by-step explanation:
See attachment
One can also solve this by calculation:
y=2x-9
y=-2x-1
-
Rearrange either equation to find x. I'll use the first:
y=2x-9
2x = y+9
x = (y+9)/2
Now use this value of x in the second equation:
y = -2x-1
y =-2((y+9)/2)-1
y = (-2y-18)/2)-1
y = -y -9 - 1
2y = -10
y = -5
Now use -5 for y in the rearranged equation:
y = -2x-1
-5 = -2x-1
-2x = -4
x = 2
Solution is (2,-5)
But the question wants a graph solution, which is also fun when you use DESMOS.