Question

уравнение помогите пожалуйста

Answer 1

1) b=25 2) a=75 .....................

Answer 2

$1) \: 25 \times \frac{3b + 28}{25} = 4 \times 25 \\ 3b + 28 = 100 \\ 3b = 100 - 28 \\ 3b = 72 \\ b = \frac{72}{3} \\ b = 24$
$2) \: \frac{3a}{4} = 15 \\ 4 \times \frac{3a}{4} = 15 \times 4 \\ 3a = 60 \\ a = \frac{60}{3} \\ a = 20$