Question

помогите пожалуйста с 86и87 заранее спасибо

Answer 1

#86
$9x = \frac{2}{5} \\ 9x \div 9 = \frac{2}{5} \div 9 \\ = \frac{2}{5} \times \frac{1}{9} \\ x = \frac{2}{45}$
$3x = 2 \times \frac{1}{7} \\ 3x = \frac{15}{7} \\ 3x \div 3 = \frac{15}{7} \div 3 \\ x = \frac{5}{7}$
$\frac{1}{2} x = 3 \\ \frac{1}{2} x \times 2 = 3 \times 2 \\ x = 6$
$\frac{3}{4} x = \frac{1}{2} \\ \frac{4}{3} \times \frac{3}{4} = \frac{4}{3} \times \frac{1}{2} \\ x = \frac{2}{3} \\ x = 0.6$