Tolong jawab pake cara dongg

A. 180 = x + 10 + x + 20
180 = 2x +30
180-30 = 2x
150 =2x
75 = x
B. sudut abc = x + 10
= 75 + 10
= 85
C. sudut cbd = x + 20
= 75 + 20
= 95