Resposta:
1 ) 3
2) -5
3) 3
4) -5/2
5) 20
6) 5
Explicação passo a passo:
1 : 11x-13 =20
11x = 20+13
11x =33
x= 3
2: 17x+50 =7x
17x-7x = -50
10x = -50
x= -50/10
x= -5
3: 9x+8 = 5x+20
9x-5x=20-8
4x=12
x=3
4: 12x+21= 10x+16
12x-10x=16-21
2x= -5
x= -5/2
5: 4x+2(3-x) = 46
4x+6-2x=46
2x= 46-6
2x=40
x=20
6: 2x/5 = 6/3
x= 6/3 . 5/2
x=5
