Выполните сложение (2a-b)/a+b/a Представьте в виде дроби (5x-6y)/2xy-(5x-3y)/2xy...

1.
$\frac{2a-b}{a} + \frac{b}{a} = \frac{2a-b+b}{a} = \frac{2a}{a} =2$

2.
$\frac{5x-6y}{2xy} - \frac{5x-3y}{2xy} = \frac{5x-6y-(5x-3y)}{2xy} = \frac{5x-6y-5x+3y}{2xy} = \frac{(5x-5x) +(-6y+3y)}{2xy} = \\ \\ = \frac{-3y}{2xy} =- \frac{3}{2x}$

3.
$\frac{25}{5-m} - \frac{m^2}{5-m} = \frac{25-m^2}{5-m} = \frac{5^2-m^2}{5-m} = \frac{(5-m)(5+m)}{5-m} = \frac{5+m}{1} = m + 5 \\ \\$