Maka nilai 2x + 20 adalah ??? Pake cara tolong

3x+10°+2x+20°=180°
5x+30°=180
5x=180-30= 150
x=30°

2x+20°= 2(30)+20=60+20=80°

( 3x + 10 ) + ( 2x + 20 ) = 180°
5x + 30 = 180°
5x + 30 - 30 = 180 - 30
5x = 150°
x = 150 ÷ 5
x = 30°


Maka Nilai 2x + 20 :
( 2 × 30 ) + 20 = 60 + 20 = 80°