Answer:
∠B = 76°
Step-by-step explanation:
Supplementary angles add up to 180 degrees, so we know that angles A and B add up to 180.
We can set up an equation and solve for x:
(x + 15) + (x - 13) = 180
Add like terms:
2x + 2 = 180
2x = 178
x = 89
Now, we can plug in 89 as x to find the measure of angle B:
x - 13
89 - 13
= 76
= 76°