i dont know how to solve these

Answer:
137°
Step-by-step explanation:
So, both are equal to each other due to them being the same degree angle.
5x+7=8x-71
subtract 5x on both sides
7=3x-71
add 71 to both sides
77=3x
divide both sides by 3
77/3=x
x equals about 26
insert x into the problems
[5(26)+7]°
this equals 137°
[8(26)-71]°
this equals 137°