Respuesta :

Answer:

x=20 degrees

Step-by-step explanation:

complementary means the angles equal 90 degrees

so ∠A+∠B=90 degrees

∠A=3x-2 and ∠B=x+12

so subsitute

(3x-2)+(x+12)=90

then solve for x

4x+10=90

4x=80

x=20 degrees is your answer