Решение
Сложение и вычитание алгебраических дробей
1) 2/y - x/(x - 5) = (2x - 10 -xy) / [y*( x - 5)]
2) (a+3)(a+) -(a)(a+1) = [(a + 3)*(a + 1) - (a + 2)²] / [(a + 2)*(a + 1)] =
= (a² + 4a + 3 - a² - 4a - 4) / [(a + 2)*(a + 1)] = - 1/ [(a + 2)*(a + 1)]
3) 3y/(y² + 4y + 4) + 3(y+2) = 3y/(y + 2)² + 3(y+2) = (3y + 3y + 2) / (y + 2)² =
(3y + 6) / (y + 2)² = 3/(y + 2)