Question

Resolva as equações.

a) -3(3x-42) = 2(7x-52)
b) x/2 + 1-x/5 = 1/2
c) x+3/2 + x+2/3 = -1/2
d) 3+x/2 - (1-x) = x-1/4

Answer 1

Explicação passo-a-passo:

$a) \: - 9x + 126 = 14x - 104 \\ - 9x - 14x = - 126 - 104 \\ = - 23x = - 230 \\ 23x = 230 \\ x = 10$

$b) \: \frac{x}{2} + 1 - \frac{x}{5} = \frac{1}{2} \\ \frac{5x + 10 - 2x = 5}{10} \\ 5x + 10 - 2x = 5 \\ 3x = 5 - 10 \\ 3x = - 5 \\ x = - \frac{5}{3}$

$c) \: x + \frac{3}{2} + x + \frac{2}{3} = - \frac{1}{2} \\ \frac{6x + 9 + 6x + 4 = - 3}{6} \\ 6x + 9 + 6x + 4 = - 3 \\ 12x + 13 = - 3 \\ 12x = - 16 \\ x = - \frac{4}{3}$

$d) \: 3 + \frac{x}{2} - (1 - x) = x - \frac{1}{4} \\ 3 + \frac{x}{2} - 1 + x = x - \frac{1}{4} \\ \frac{12 + 2x - 4 + 4x = 4x - 1}{4} \\ 12 + 2x - 4 + 4x = 4x - 1 \\ 2x - 4x + 4x = - 9 \\ 2x = - 9 \\ x = - \frac{9}{2} \\ x = - 4.5$