Question

resolva as seguintes equaçoes :
a] 3 x -7 = 2 x + 7
b] 4 x - 15 = - 2 x + 3
c] 7 x - 4 - x = - 2 x + 8 - 3 x
e] - x - 5 + 4 x = - 7 x + 6 x + 15
f] 7 [ x - 5 ] = 3 [ x + 1 ]
g] 2 [ x + 1 ] - [ x - 1 ] = 0

Answer 1

a]
3x - 7 = 2x + 7 
3x - 2x = 7 + 7
x = 14

b]
4x - 15 = - 2x + 3 
4x + 2x = 3 + 15
6x = 18
x = 18/6
x = 3

c]
7x - 4 - x = - 2x + 8 - 3x 
6x - 4 = - 5x + 8
6x + 5x = 8 + 4
11x = 12
x = 12/11

e]
- x - 5 + 4x = - 7x + 6x + 15
3x - 5 = - x + 15
3x + x = 15 + 5
4x = 20
x = 20/4
x = 5

f]
7(x - 5) = 3(x + 1)
7x - 35 = 3x + 3
7x - 3x = 3 + 35
4x = 38 (:2)
2x = 19
x = 19/2 

g]

2(x + 1) - (x - 1) = 0
2x + 2 - x + 1 = 0
2x - x + 2 + 1 = 0
x + 3 = 0
x = - 3