Question

Como resolve as equações:
a) 5x-3 (x+2)=15
b) 2x+3x+9=8 (6-x)
c) 4 (x+10)-2 (x-5)=0

Answer 1

a) 5x-3*(x+2)=15 
5x-3x-6=15
2x=21
x=21/2
x=10,5

b) 2x+3x+9=8*(6-x) 
5x+9=48-8x
13x=39
x=39/13
x=3

c) 4*(x+10)-2*(x-5)=0
4x+40-2x+10=0
2x+50=0
2x=-50
x=-50/2
x=-25