Answer:
It -1
Step-by-step explanation:
I already had this question and I got it right
It should equal to 180 so 180-157=23
You answered all of them if there is only 45 and you answered 810810.
We know the perimeter is the total sum of all sides of the shape, we can use this to form an equation: the perimeter=1st side + 2nd side + 3rd side + 4th side 39a-7=9a+(5a+1)+(17a-6)+4th side.
Collect like terms to get 39a-7=31a-5+4th side
If we move everything but the 4th side over to the left we can solve
C. 8a-2=4th side is the correct answer
