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
The answer is c. You double the number for finding radius
The answer is: [C]: " (x - 4) " .
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" (x+9)(x-4) = x² - 4x + 9x - 36 = x² + 5x - 36 " .
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The answer i choose is $5.50 because i added $3.00 and $2.50. so thats how i got my answer
Answer:
The point (2,12) is not a solution of the system
see the explanation
Step-by-step explanation:
we have
----> equation A
----> equation B
Solve the system by elimination
Adds equation A and equation B

Find the value of y
substitute the value of x in the equation A

The solution of the system is the point (-2,-8)
The system has only one solution, because the intersection point both lines is only one point
therefore
The point (2,12) is not a solution of the system