Find the value of x. then find the measure of each labeled angle.

(answer choices below! )

a) x= 15; both labeled angles are 55°.

b) x= 25; both labeled angles are 65°.

c) x= 37.5; the labeled angles are 37.5° and 142.5°.

d) x= 37.5; the labeled angles are 77.5° and 102.5°.

Both angles WILL have the same measure.

So,

3x-10= x+40 (you have to set the equations equal to one another)

Now, add 10 to both sides.

3x=x+50

Subtract x on both sides.

2x=50

Divide both sides by 2.

x=25

Now, plug in x.

(25 +40)= 65

(3(25)-10)= 65

x equals 25 and both angles are equal to 65. Or "B".

I hope this helps!
~cupcake