Question

algm ajuda pfv é prova pra hj pfvv​

Answer 1

Resposta:

b) 9

c) 36, 37 e 38

d) R$ 800,00

Explicação passo-a-passo:

b) 3 · x + 13 + (x - 1) = 48 -> 3x + 13 + x - 1 = 48

4x + 12 = 48 -> 4x = 36 -> x = 9

c) x + (x + 1) + (x + 2) = 111 -> x + x + 1 + x + 2 = 111

3x + 3 = 111 -> 3x = 108 -> x = 36, x + 1 = 37, x + 2 = 38

d) x = 3/10 · x + 1/4 · x + 1/10 · x + 280

x = 3x/10 + x/4 + x/10 + 280

20x/20 = 6x/20 + 5x/20 + 2x/20 + 5600/20

20x = 6x + 5x + 2x + 5600 -> 20x = 13x + 5600

7x = 5600 -> x = R$ 800,00