Respuesta :

TheLazyNobita

All angles are of triangle and thus give sum of 180⁰

x + 5 + 7x - 5 + x = 180⁰

9x = 180⁰

x = 20⁰

Answer:

it's 20

Step-by-step explanation:

(X+5)° + (7x-5)° + x°= 180° { sum of the three angles of the triangle is 180°}

X+5+7x-5+X = 180

X+7x+X+5-5= 180

9x+0 = 180

9x = 180

therefore X= 180/9

= 20