For :
So
Answer:
45°
Step-by-step explanation:
size of each angle = 360°÷8
8 are the number of sides
you get 45°
5 +3(y-4) = 4y +10
5 + 3y -12= 4y +10
-7 +3y = 4y + 10
3y - 4y = 10 + 7
-y = 17
y= -17