Find the slope first:
m=y2-y-1/x2-x1
m=2-10/-3-1
m= -8/-4
m= 2
Select a point & put into y=mx+b to find b.
y=mx +b
10 =2(1) + b
10 =2 +b
8 = b
Rewrite the equation with your slope &intercept:
y=2x + 8
That's ^ the equation that describes your line!
I do believe that the answer is 9.<span />
Since the interior is 170 the exteriro must be 10 degrees. There is a total of 360 degrees so 360/10=36 or 36 sides.
