Question

alguem me ajuda nessas contas?

a)2(7x+2)+12(x+1)=2
b)3(2x-5)=9-2x
c)10-4x=9-2x

Answer 1

A

2(7x + 2) + 12(x + 1)= 2

14x + 4 + 12x + 12= 2

14x + 12x= 2 - 4 - 12

26x= - 14

x= -14/26>> ÷ 2

x= - 7/13

B

3(2x - 5)= 9 - 2x

6x - 15= 9 - 2x

6x + 2x= 9 + 15

8x= 24

x= 24/8

x= 3

C

10 - 4x= 9 - 2x

- 4x + 2x= 9 - 10

- 2x= - 1>> .(-1)

2x= 1

x= 1/2

Answer 2

Olá...

Resolução:

a)

2(7x + 2) + 12(x + 1) = 2

14x + 4 + 12x + 12 = 2

26x + 16 = 2

26x = 2 - 16

26x = - 14

x = - 14/26

x = - 7/13

b)

3(2x - 5) = 9 - 2x

6x - 15 = 9 - 2x

6x + 2x = 9 + 15

8x = 24

x = 24/8

x = 3

c)

10 - 4x = 9 - 2x

- 4x + 2x = 9 - 10

- 2x = - 1⇒(- 1)

2x = 1

x = 1/2

Boas lições.