Respuesta :

3x + 9x = 180

12x = 180

x = 15

Angle 1 = 3x

3(15) = 45

B. 45°

vinavratil

T he answer is B 45 degrees

explanation

set up an equation

3x + 9x = 180

solve for x

x = 180/12 = 15

so, the angle 9x is 135 degrees

angle 1 is supplementary so, :

<1 = 180 - 135 = 45