Question

qual é a resposta?
a) 3x-21=6
b) 4x-3-x+8=11
c) 6.(x-2)=12
d) 9+2.(5x.4)=21

Answer 1

a) 3x-21 = 6
3x = 6+21
3x = 27
x = 27/3
x = 9

b) 4x-3-x+8 = 11
4x-x = 11+3-8
3x = 14-8
3x = 6
x = 6/3
x = 2

c) 6.(x-2) = 12
6x-12 = 12
6x = 12+12
6x = 24
x = 24/6
x = 4

d) 9+2.(5x.4) = 21
9+10x+8 = 21
10x = 21-8-9
10x = 21-17
10x = 4
x = 4/10
x = 0,4

Answer 2

a)3x-21=6
    3x=6+21
    3x=27
    x=27/3
    x=9
b)4x-3-x+8=11
   4x-x=11+3-8
    4x=6
    x=6/4
    x=3/2
c)6.(x-2)=12
   6x-12=12
   6x=12+12
   6x=24
  x=24/6
x=4
d)9+2.(5x.4)=21
   9+40x=21
   40x=21-9
   40x=12
x=12/40
x=3/10