Question

a) 3.×-9=3 b x+8+3x=24 c) 12.(x-3)=30.(x+12) d) 10x-20=×+1 e) 4.(x-7)=2.(x+3) f) 20x=16.(x+1)

Answer 1

a) 3x-9=3
    3x= 3 + 9
   3x= 12
     x = 12: 3 = 4
    x=4

b)x+8+3x=24
   4x= 24 -8
   4x= 16
    x= 16:4 = 4
   x = 4

c)12 (x -3) = 30 (x+12)
  12x -36 = 30x +360
  12x - 30x = 360 + 36
  - 18x = 396
    x = 396 : - 18 = 22
    x= 22


d)10x - 20 = x + 1
10x -x =1 +20
9x = 21
x= 21:9 (simplifica por 3)  7:3
resposta > x = 7:3

e)4 (x-7) = 2(x+3)
4x -28 = 2x +6
4x - 2x = 6 + 28
2x + 34
x= 34:2 = 17
x=17

f) 20x=16(x+1)
20x = 16x + 16
20x - 16x = 16
4x = 16
x= 16:4 
x=4