Question

qual o valor de x e explique com chegou a esse resultado


a)5x+3x=16

b)x+x+8=54

c)7x-2-5x=18

d)12x-10x-4=3

e)8x=5x+4,5

f)4(X+1)=12

g)5(3-x)-4x=18

h)9x-3(2x+2)=15

i)2,5(x-2)-1,5x=1

j)2,5x+8=2(x+7)

Answer 1

Oi...

a)

5x + 3x = 16

8x = 16

x = 16/8

x = 2

b)

x + x + 8 = 54

2x + 8 = 54

2x = 54 - 8

2x = 46

x = 46/2

x = 23

c)

7x - 2 - 5x = 18

2x - 2 = 18

2x = 18 - 2

2x = 16

x = 16/2

x = 8

d)

12x - 10x - 4 = 3

2x - 4 = 3

2x = 3 + 4

2x = 7

x = 7/2

e)

8x = 5x + 4,5

8x - 5x = 4,5

3x = 4,5

x = 4,5/3

x = 1,5

f)

4(x + 1) = 12

4x + 4 = 12

4x = 12 - 4

4x = 8

x = 8/4

x = 2

g)

5(3 - x) - 4x = 18

15 - 5x - 4x = 18

- 9x = 18 - 15

- 9x = 3 ⇒(× por - 1)

9x = - 3

x = - 3/9 ÷ 3

x = - 1 /3

h)

9x - 3(2x + 2) = 15

9x - 6x - 6 = 15

3x - 6 = 15

3x = 15 + 6

3x = 21

x = 21/3

x = 7

i)

2,5(x - 2) - 1,5x = 1

2,5x - 5 - 1,5x = 1

x - 5 = 1

x = 1 + 5

x = 6

j)

2,5x + 8 = 2(x + 7)

2,5x + 8 = 2x + 14

2,5x - 2x = 14 - 8

0,5x = 6

x = 6/0,5

x = 12

Espero ter ajudado.