Question

resolva as equações
2(x-1)+4(x+1)=0
x+x/2+3x=90
1/3+3x=100
3x-28-x+13=2x-13
10x-2x=64

Answer 1

2(x-1)+4(x+1)=0
2*x +2*(-1) + 4*x + 4*1 = 0
2x -2 + 4x + 4 = 0
6x = -4+2
6x = -2
x=-2/6
x=-0,3333...

x + x/2 + 3x=90
x + x + 3x = 90
1   2     1       1
mmc = 2
2x + x + 6x = 180
9x = 180
x=180/9
x=20

1/3+3x=100
1 + 3x = 100
3     1       1
mmc = 3
1 + 9x = 300
9x= 299
x=299/9
x = 33,2222222222222222222222222...

3x-28-x+13=2x-13
3x -x -2x = -13 + 28 - 13
0x = 28

10x-2x=64
8x = 64
x=64/8
x=8