Question

Resolva as equações a seguir:
a) 2x+8=x-5
b)30x-10=16x+26
c)2(x+1)+15=27
d)-7x+3(x+4)=2x-18
e)16-4x=-9(x+5)

Answer 1

a) 2x + 8 = x - 5
2x - x = - 5 - 8
x = - 13

b)30x - 10 = 16x + 26
30x - 16x = 26 + 10
14x = 36 (÷2)
7x = 18
x = 18/7


c)2(x + 1 ) + 15 = 27
2x + 2 + 15 = 27
2x = 27 - 2 - 15
2x = 25 - 15
2x =10
x = 10/2
x =5

d)- 7x + 3(x + 4) = 2x - 18
- 7x + 3x + 12 = 2x - 18
- 4x - 2x = - 18 - 12
- 6x = - 30
x =- 30 / - 6
x = 5

e)16 - 4x = - 9(x + 5)
16 - 4x = - 9x - 45
- 4x + 9x = - 45 - 16
5x = - 61
x = - 61/5
x = - 12,2

Answer 2

Vamos lá

a) 2x+8=x-5

2x - x = -5 - 8

x = -13

b) 30x-10=16x+26

30x - 16x =  26 + 10

14x = 36

x = 36/14 = 18/7

c)2(x+1)+15=27

2x + 2 + 15 = 27

2x = 27 - 17 = 10

x = 5

d)-7x+3(x+4)=2x-18

-7x + 3x + 12 = 2x - 18

2x + 7x - 3x = 12 + 18

6x = 30

x = 5

e) 16-4x=-9(x+5)

16 - 4x = -9x - 45

9x - 4x = -45 - 16

5x = -61

x = -61/5