Question

-Resolva as equações:
a) 9x-3 (2x+2)=15
b) 2,5 (x-2)-1,5x=1
c) 3,5x+8=2 (x+7)
d) 6 (3x+2)-8=-2
e)-3 (x-5)-2 (2x+1)=-8

Answer 1

a) 9x-3 (2x+2)=15
9x-6x-6=15
3x=15+6
x=21/3=7

b)2,5 (x-2)-1,5x=1
2,5x-5-1,5x=1
x=6

c)3,5x+8=2(x+7)
3,5x+8=2x+14
1,5x=6
x=4

d)6(3x+2)-8=-2
18x+12-8=-2
18x=-2-4
x=-3

e)-3 (x-5)-2 (2x+1)= -8
-3x+15-4x-2=-8
-7x=-8-13 
-7x=-21 (multiplicando por -1)
7x=21
x=3