220 Вправа 220Алгебра 8 клас Бевз 2025 · § 5 · стор. 50

220. Виконай множення.

а) ${\displaystyle \frac{x}{y}\cdot \frac{z}{t}=}$${\displaystyle \frac{x\cdot z}{y\cdot t}=}$${\displaystyle \frac{xz}{yt}}$;

б) ${\displaystyle \frac{2a}{b}\cdot \frac{m}{n}=}$${\displaystyle \frac{2a\cdot m}{b\cdot n}=}$${\displaystyle \frac{2am}{bn}}$;

в) ${\displaystyle \frac{1}{a}\cdot \frac{1}{x}=}$${\displaystyle \frac{1}{a\cdot x}=}$${\displaystyle \frac{1}{ax}}$;

г) ${\displaystyle \frac{4a}{c}\cdot \frac{x}{3}=}$${\displaystyle \frac{4a\cdot x}{c\cdot 3}=}$${\displaystyle \frac{4ax}{3c}}$;

ґ) ${\displaystyle \frac{3}{2b}\cdot \frac{6b}{c}=}$${\displaystyle \frac{3\cdot 6b}{2b\cdot c}=}$${\displaystyle \frac{3\cdot 3\cdot \cancel{2}\cancel{b}}{\cancel{2}\cancel{b}\cdot c}=}$${\displaystyle \frac{9}{c}}$;

д) ${\displaystyle \frac{x^3}{3}\cdot \frac{9}{x^4}=}$${\displaystyle \frac{x^3\cdot 9}{3\cdot x^4}=}$${\displaystyle \frac{\cancel{x^3}\cdot 3\cdot \cancel{3}}{\cancel{3}\cdot x\cancel{x^3}}=}$${\displaystyle \frac{3}{x}}$;

е) ${\displaystyle \frac{m^2}{10}\cdot \frac{5}{m}=}$${\displaystyle \frac{m^2\cdot 5}{10\cdot m}=}$${\displaystyle \frac{m\cancel{m}\cdot \cancel{5}}{2\cdot \cancel{5}\cdot \cancel{m}}=}$${\displaystyle \frac{m}{2}}$;

є) ${\displaystyle \frac{8a^2}{5}\cdot \frac{25}{4a}=}$${\displaystyle \frac{8a^2\cdot 25}{5\cdot 4a}=}$${\displaystyle \frac{2\cdot \cancel{4}a\cancel{a}\cdot 5\cdot \cancel{5}}{\cancel{5}\cdot \cancel{4}\cancel{a}}=}$${\displaystyle 10a}$.