Respostas

2013-12-23T12:00:27-02:00
A)
2X = 13-3
X = 11/2

B)
-3X-X = 13-19
-4X = -6
X = 6/4 = 3/2

C)
-3X+X = 13-9
-2X = 4
X = -2

D)
2X-8X = -10-2
-6X = -12
X = 2

E)
Y+Y = 3+7+2
2Y = 12
Y = 6

F)
2X+X = -3-6
3X = -9
X = -3

G)
-X+2X = -10-3-2
X = -15

Espero ter ajudado, bom estudo!