Question

qual o valor do "x" 30-20+2x=10

Answer 1

30-20+2x=10
2x=10+20-30
2x=10-10
2x=0
x=0/2
x=0

Answer 2

30-20+2x=1030 - 20 - 10 = - 2x
30 - 30 = -2x
0 = -2x
x = 0/(-2)