paulodamaia

a)2y+8 =

2y = - 8

y = - 8 / 2

y = - 4

b)5x+3 =

5x = - 3

x = - 3 / 5

x = - 0,6

c)2xy+x =

x = - 2xy

d)1/2x+z =

z = - 1 /2 x