WILL MARK BRAINLIEST! Can someone please help! I don't understand some of these questions :(

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Step-by-step explanation:

The interior and exterior angle of a polygon is supplementary

let interior be I

let exterior be E

I + E = 180

Since the interior angle is 8 times that of an exterior angle,

8E + E = 180          [replacing I with 8E]  

9E = 180                

E = 20                      

The exterior angle is 20 degrees

I + E = 180          

I + 20 = 180      

I = 160              

The interior angle is 160 degrees.

The equation to find the interior angle of a polygon with 'n' number of sides is:

I = ( (n − 2) × 180 ) ⁄ n

We know the interior angle, so plug it in and solve for n:

160 = ( (n − 2) × 180 ) ⁄ n      

160n = (n − 2) × 180            

160n = 180n − 360                  

-20n = -360                            

n = 18                                  

7 ft 6 in means 7 1/2, because 6 in is 1/2 of a foot. 7 ft 8 in means 7 2/3 because 8 in is 2/3 of a foot. 23/3 = 7 2/3. 15/2 = 7 1/2.

23/3   *   15/2   = 57 1/2

step-by-step explanation: