Question

What is the measure of ∠B?

Answer 1

Answer:

m<B = 60

Step-by-step explanation:

Exterior angle thm:

3x + 4x = 10x - 45

7x = 10x - 45

7x - 10x = -45

-3x = -45

x = 15

<B:

4x

4(15)

60