Question

Calcule o valor X em cada equação abaixo:

a) 2x - 4 + 6 = 20

b) -15 + 5x = 25

c) 5x + 2x + 4x = 121

d) 7x - 2 = 5x + 10
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Answer 1

Resposta:

a) x = 9

b) x = 8

c) x = 11

d) x = 6

Explicação passo a passo:

a) 2x - 4 + 6 = 20

2x + 2 = 20

2x + 2 - 2 = 0

2x = 20 - 2

2x = 18

x = 18:2

x = 9

b) - 15 + 5x = 25

- 15 + 5x - 15 = 0

5x = 25 + 15

5x = 40

x = 40:5

x = 8

c) 5x + 2x + 4x = 121

11x = 121

x = 121:11

x = 11

d) 7x - 2 = 5x + 10

7x - 2 + 2 = 0

7x = 5x + 10 + 2

7x = 5x + 12

7x - 5x = 12 - 5x

2x = 12

x = 12:2

x = 6