Respuesta :

Answer:  B. 40

For any triangle, the three angles always add to 180

(y+10)+(2y)+(50) = 180

3y+60 = 180 ... combine like terms

3y+60-60 = 180-60 ... subtract 60 from both sides

3y = 120

3y/3 = 120/3 .... divide both sides by 3

y = 40