Question

como eu resolvo
1) Resolva as equações:
a) 2(2x + 1) = 30
b) –(3x + 4) = (3 – 5x)
c) 8(10−k)=2k
d) 2x – 3(4 – x) = 5 + 4(2x + 1)
e) 2(x – 3) + 4(2x + 1) = 8 – 5(x – 4)
f) +(4x – 5) = -3(x – 4)

Answer 1

Resposta:

a)

2.2x=4x+2.1=2

4x +2 = 30

4x = 30 -2

4x = 28

x = 28/4

x =7

b) - 3x - 4 = 3 - 5x

-3x + 5x = 3 + 4

2x = 7

x = 7/2

c) 80 - k = 2k

80 = 2k - k = k

k = 80

d) 2x - 3.4 +3x 5 + 4.2x= 8 + 4.1= 4

2x - 12 +3x = 5 + 8x + 4

5x - 12 = 8x + 4

5x - 8x = 4 + 12

-3x = 21 (-1)

3x = - 21

x = - 21/ 3

x = -7

e) 1° conta 2x +2.(-3) = -6 + 4.2x = 8x+ 4.1 =4

=( 2x -6+8x+4) = 10 x - 2

2° conta 8 - 5x +(5.4 = 20)

8 - 5x +20 = - 5x + 28

vai ficar :

10x - 2 = - 5x + 28

10x + 5x = 28 + 2

15x = 30

x = 30/ 15

x =2

f) 4x - 5 = - 3x + 12

4x + 3x = 12 + 5

7x = 17

x = 17 / 7

Desculpa se tiver algum erro :)