Question

8) Resolva as equações:
a) 1- x + 5 = 8
b) 0 = x + 12
c) 2x = 14
d) 4x = −12
e) 6x = 2x + 16
f) 2x − 5 = x + 1
g) 2x + 1 = 4x − 7
h) 9x + 9 + 3x = 15
i) 4x − 1 = 3(x − 1)
j) 3(x − 2) = 2x − 4
k) 7(x − 4) = 2x − 3
l) 3(x − 2) = 4(3 − x)
m) 3(3x − 1) = 2(3x + 2)
n) 7(x − 2) = 5(x + 3)
o) 3(2x − 1) = −2(x + 3)
p) 5x − 3(x + 2) = 15
q) 2x + 3x + 9 = 8(6 − x)

Answer 1

Resposta:Segue as contas abaixo na explicação

Explicação passo-a-passo:

a) 1- x + 5 = 8

    -x+6=8

    -x=8-6

    -x=2(-1)

     x=-2

b) 0 = x + 12

   -x=12(-1)

    x=-12

c) 2x = 14

  x=14/2

  x=7

d) 4x = −12

    x=-12/4

    x=-3

e) 6x = 2x + 16

   6x-2x=16

   4x=16

   x=16/4

   x=4

f) 2x − 5 = x + 1

   2x-x=1+5

   x=6

g)2x + 1 = 4x − 7

  2x-4x=-7-1

  -2x=-8(-1)

  2x=8

  x=8/2

  x=4

h) 9x + 9 + 3x = 15

    12x+9=15

    12x=15-9

    12x=-6

    x=-6/12:6/6

    x=-1/2

i) 4x − 1 = 3(x − 1)

  4x-1=3x-3

  4x-3x=-3+1

   x=-2

j) 3(x − 2) = 2x − 4

  3x-6=2x-4

  3x-2x=-4+6

  x=2

k) 7(x − 4) = 2x − 3

   7x-28=2x-3

   7x-2x=-3+28

   5x=25

   x=25/5

   x=5

l) 3(x − 2) = 4(3 − x)

  3x-2=12-4x

  3x+4x=12+2

  7x=14

  x=14/7

  x=2

m) 3(3x − 1) = 2(3x + 2)

    9x-3=6x+4

    9x-6x=4+3

    3x=7

    x=7/3

n) 7(x − 2) = 5(x + 3)

   7x-14=5x+15

   7x-5x=15+14

   2x=29

   x=29/2

o)3(2x − 1) = −2(x + 3)

  6x-3=-2x-6

  6x+2x=-6+3

  8x=-3

  x=-3/8

p) 5x − 3(x + 2) = 15

   5x-3x-6=15

   2x-6=15

   2x=15+6

   2x=21

   x=21/2

q) 2x + 3x + 9 = 8(6 − x)

   5x+9=48-8x

   5x+8x=48-9

   13x=39

   x=39/13

   x=3

Answer 2

Oi, boa tarde!

Resposta:

8) a) x = – 2.

b) x = – 12.

c) x = 7.

d) x = – 3.

e) x = 4.

f) x = 6.

g) x = 4.

h) x = 1/2.

i) x = – 2.

j) x = 2.

k) x = 5.

l) x = 18/7.

m) x = 7/3.

n) x = 29/2.

o) x = (– 3)/8.

p) x = 21/2.

q) x = 3.

Explicação passo-a-passo:

8) a) 1 – x + 5 = 8

– x = 8 – 1 – 5

– x = 8 – 6

– x = 2 · (– 1)

x = – 2.

b) 0 = x + 12

– x = 12 – 0

– x = 12 · (– 1)

x = – 12.

c) 2x = 14

x = 14/2

x = 7.

d) 4x = – 12

x = (– 12)/4

x = – 3.

e) 6x = 2x + 16

6x – 2x = 16

4x = 16

x = 16/4

x = 4.

f) 2x – 5 = x + 1

2x – x = 1 + 5

x = 6.

g) 2x + 1 = 4x – 7

2x – 4x = – 7 – 1

– 2x = – 8 · (– 1)

2x = 8

x = 8/2

x = 4.

h) 9x + 9 + 3x = 15

9x + 3x = 15 – 9

12x = 6

x = 6/12 ---> Simplificando "6/12" por 6:

x = 1/2.

i) 4x – 1 = 3(x – 1)

4x – 1 = 3x – 3

4x – 3x = – 3 + 1

x = – 2.

j) 3(x – 2) = 2x – 4

3x – 6 = 2x – 4

3x – 2x = – 4 + 6

x = 2.

k) 7(x – 4) = 2x – 3

7x – 28 = 2x – 3

7x – 2x = – 3 + 28

5x = 25

x = 25/5

x = 5.

l) 3(x – 2) = 4(3 – x)

3x – 6 = 12 – 4x

3x + 4x = 12 + 6

7x = 18

x = 18/7.

m) 3(3x – 1) = 2(3x + 2)

9x – 3 = 6x + 4

9x – 6x = 4 + 3

3x = 7

x = 7/3.

n) 7(x – 2) = 5(x + 3)

7x – 14 = 5x + 15

7x – 5x = 15 + 14

2x = 29

x = 29/2.

o) 3(2x – 1) = – 2(x + 3)

6x – 3 = – 2x – 6

6x + 2x = – 6 + 3

8x = – 3

x = (– 3)/8.

p) 5x – 3(x + 2) = 15

5x – 3x – 6 = 15

5x – 3x = 15 + 6

2x = 21

x = 21/2.

q) 2x + 3x + 9 = 8(6 – x)

2x + 3x + 9 = 48 – 8x

2x + 3x + 8x = 48 – 9

13x = 39

x = 39/13

x = 3.

Espero ter te ajudado e bons estudos para você! ;)