Question

calcule as proporções:2x-5/7x = 3/10

Answer 1

Resposta:

$\frac{2x - 5}{7x} = \frac{3}{10} \\ \\ 10 \times (2x - 5) = 21x \\ 20x - 50 = 21x \\ 20x - 50 - 21x = 0 \\ - x - 50 = 0 \\ - x = 50 \times ( - 1) \\ x = - 50$