80 Вправа 80Алгебра 8 клас Бевз 2025 · § 2 · стор. 21

80. НМТ. Спрости вираз.

а) ${\displaystyle \frac{9-x^2}{x^2+6x+9}=}$${\displaystyle \frac{(3-x)\cancel{\left(3+x\right)}}{(x+3)\cancel{\left(x+3\right)}}=}$${\displaystyle \frac{3-x}{x+3}}$;

б) ${\displaystyle \frac{25+10b+b^2}{5b^2+25b}=}$${\displaystyle \frac{(b+5)\cancel{\left(b+5\right)}}{5b\cancel{\left(b+5\right)}}=}$${\displaystyle \frac{b+5}{5b}}$;

в) ${\displaystyle \frac{{(2x-3)}^2-9}{x}=}$${\displaystyle \frac{(2x-3-3)(2x-3+3)}{x}=}$${\displaystyle \frac{(2x-6)\cdot 2\cancel{x}}{\cancel{x}}}$=

=${\displaystyle 2(2x-6)=}$${\displaystyle 4x-12}$.