Question

Resolva as equações
A) x-3x-4=6x+45
B) (2x-1).3=5(-x+2x)
C) 2x/2+ 4x/3=1/2
D) (5x-3).(-3)=4
E) x-2x=4x/2-4

Answer 1

A)
x - 3x - 4 = 6x + 45
- 2x - 4 = 6x + 45
- 4 - 45 = 6x + 2x
- 49 = 8x
8x = - 49
x = - 49/8

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B)
(2x - 1).3 = 5.(- x + 2x)
6x - 3 = 5.(x)
6x - 3 = 5x
6x - 5x = 3
x = 3

**************************
C)
2x/2+ 4x/3=1/2

x +  4x   =  1
      ------    ----
         3        2

6x + 2.4x = 3.1
------------    ------
     6              6

6x + 8x = 3
14x = 3
x = 3/14

*************************
D)
(5x - 3).(-3) = 4
- 15x + 9 = 4
- 15x = 4 - 9
- 15x = - 5 (-1)
  15x = 5
x =   5  (:5)
       -----
       15  (:5)

x =  1
      ------
        3

***********************
E)
x - 2x = 4x/2 - 4
- x =   2x - 4
- x - 2x = - 4
- 3x = - 4  (-1)
3x = 4
x = 4/3