Question

Решите уравнение (7у + 18)(3,6 – 0,3y) = 0.

Answer 1

$\displaystyle (7y+18)(3,6-0,3y)=0\\\\(7y+18)(\frac{18}{5}-\frac{3}{10}y)=0\\ \\7y+18=0,\frac{18}{5}-\frac{3}{10}y=0\\ \\y_1=-\frac{18}{7},y_2=12$