Question

resolva as expressões
b) 2x+3 x-3
_______+______=5
2 3


d) 2x+3 x+2
______ -______=x
5 3

Answer 1

letra b
$\frac{2x + 3}{2} + \frac{x - 3}{5} = 5 \\ mmc = 6 \\ \frac{6x + 9}{6} + \frac{2x - 6}{6} = \frac{30}{6} \\ 6x + 9 + 2x - 6 = 30 \\ 6x + 2x = 30 + 6 - 9 \\ 8x = 36 - 9 \\ 8x = 27 \\ x = \frac{27}{8}$
letra d
$\frac{2x + 3}{5} - \frac{x + 2}{3} = x \\ mmc = 15 \\ \frac{6x + 9}{15} - \frac{5x + 10}{15} = \frac{15x}{15} \\ 6x + 9 - 5x + 10 = 15x \\ x - 1 = 15x \\ x - 15x = 1 \\ - 14x = 1 \: \times ( - 1) \\ x = \ \frac{ - 1}{14}$