142° Вправа 142Алгебра 8 клас Тарасенкова 2025 · § 4 · стор. 46

142. Виконайте віднімання дробів.

1) ${\displaystyle \frac{12}{7x}-\frac{3}{7x}=}$${\displaystyle \frac{12-3}{7x}=}$${\displaystyle \frac{9}{7x}}$;

2) ${\displaystyle \frac{11}{5a}-\frac{7}{5a}=}$${\displaystyle \frac{11-7}{5a}=}$${\displaystyle \frac{4}{5a}}$;

3) ${\displaystyle \frac{13}{9c}-\frac{5}{9c}=}$${\displaystyle \frac{13-5}{9c}=}$${\displaystyle \frac{8}{9c}}$;

4) ${\displaystyle \frac{13y}{y-1}-\frac{9y}{y-1}=}$${\displaystyle \frac{13y-9y}{y-1}=}$${\displaystyle \frac{4y}{y-1}}$;

5) ${\displaystyle \frac{4c}{c+2}-\frac{9c}{c+2}=}$${\displaystyle \frac{4c-9c}{c+2}=}$${\displaystyle -\frac{5c}{c+2}}$;

6) ${\displaystyle \frac{3x}{a+2}-\frac{14x}{a+2}=}$${\displaystyle \frac{3x-14x}{a+2}=}$${\displaystyle -\frac{11x}{a+2}}$;

7) ${\displaystyle \frac{4a}{d-1}-\frac{17a}{d-1}=}$${\displaystyle \frac{4a-17a}{d-1}=}$${\displaystyle -\frac{13a}{d-1}}$;

8) ${\displaystyle \frac{13a}{b^2+1}-\frac{18a}{b^2+1}=}$${\displaystyle \frac{13a-18a}{b^2+1}=}$${\displaystyle -\frac{5a}{b^2+1}}$.