Задача 54783 ...

5f3ea7e3faf909182968ddd9

21.10.2020 17:08:54

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1.
[m]\frac{a-7x}{a}:\frac{ax-7x6^2}{a^2}=\frac{a-7x}{a}\cdot \frac{a^2}{ax-7x^2}=\frac{a-7x}{1}\cdot \frac{a}{x\cdot (a-7x)}=\frac{a}{x}[/m]

при a=-6; x=10

[m]\frac{a}{x}=\frac{-6}{10}=-0,6[/m]

3.
[m]2b+\frac{5a-2b^2}{b}=\frac{2b^2+5a-2b^2}{b}=\frac{5a}{b}[/m]

при a=6; b=-60

[m]\frac{5a}{b}=\frac{5\cdot 6}{(-60)}=-\frac{1}{2}=-0,5[/m]