Question

resolva as equações de primeiro grau:
a) x+3+2x=12
b)x-4=9
c)x-2=3x+6
d)3x-4=2x+8
e)6x=2x+16
f)2x-5=x+1
g)2x+1=4x-7

Answer 1

Resposta:

a) x + 3 + 2x = 12

2x + x = 12 - 3

3x = 9

x = 9/3

x = 3

b) x - 4 = 9

x = 9 + 4

x + 13

c) x - 2 = 3x + 6

x - 3x = 6 + 2

- 2x = 8

x = - 2/8

x = - 4

d) 3x - 4 = 2x + 8

3x - 2x = 8 + 4

1x = 12

x = 12/1

x = 12

e) 6x = 2x + 16

6x - 2x = 16

4x = 16

x = 16/4

x = 4

f) 2x - 5 = x + 1

2x - x = 1 + 5

1x = 6

x = 6/1

x = 6

g) 2x + 1 = 4x - 7

2x - 4x = - 7 - 1

- 2x = - 8

x = -2/-8

x = 4