Respostas

A melhor resposta!
2014-09-04T15:40:58-03:00
1)
9x + 2 = 7x
2x = -2
X = -1

2)
5x + 2 = 11
5x = 9
x = 9/5

3)
4x - 12 = x
3x = +12
x = 4

4)
3x + 1 = 5x
-2x = -1 (-1)
2x = 1
x = 1/2

5)
3x - 1 = 8
3x = 9
x = 3
1 5 1
2014-09-04T15:41:45-03:00
9x+2=7x
2=9x-7x
2=2x
x=2/2
x=1

5x+2=11
5x=11-2
5x=9
x=9/5
x=1,8

4x-12=x
-12=x-4x
-12=-3x
x=-12/-3
x=12/3
x=4

3x+1=5x
1=5x-3x
1=2x
x=1/2
x=0,5

3x-1=8
3x=8+1
3x=9
x=9/3
x=3