Respuesta :

Answer:

B)10

Step-by-step explanation:

Because this is a right angle(indicated by the red box) the total measure should be 90°.

And based on that we say 5X +40=90

Subtract 40 from both sides to get 5x=50

And then divide both sides by 5 to get x=10

Answer:

x = 10°

Step-by-step explanation:

5x° + 40° = 90°

5x° = 90°-40°

5x°=50°

x°= 50°/5

x = 10°