Question

Укажи равные между собой выражения.
(-4,5)
?
2
3
-21
(-3,5) 4
-3
-2
(-2,25) (-8)
5 (-2,1) 2
18​

Answer 1

$(-4,5)*\tt\displaystyle\frac{2}{3}=\bigg(-4\frac{5}{10}\bigg)*\frac{2}{3}=\bigg(-4\frac{1}{2}\bigg)*\frac{2}{3}=\bigg(-\frac{9}{2}\bigg)*\frac{2}{3}=-\bigg(\frac{9*2}{2*3}\bigg)=\\\\=-\bigg(\frac{\not3*3*2}{\not2*\not3}\bigg)=-3$

$(-3,5)*\tt\displaystyle\frac{4}{7}=\bigg(-3\frac{5}{10}\bigg)*\frac{4}{7}=\bigg(-3\frac{1}{2}\bigg)*\frac{4}{7}=\bigg(-\frac{7}{2}\bigg)*\frac{4}{7}=-\bigg(\frac{7*4}{2*7}\bigg)=\\\\=-\bigg(\frac{\not7*\not2*2}{\not2*\not7}\bigg)=-2$

$(-2,25)*(-8)=\bigg(-2\tt\displaystyle\frac{25}{100}\bigg)*\bigg(-8\bigg)=\bigg(-2\frac{1}{4}\bigg)*(-8)=\bigg(-\frac{9}{4}\bigg)*\bigg(-8\bigg)=\\\\=\frac{9*8}{4}=\frac{9*2*\not4}{\not4}=18$

$5*(-2,1)*2=(5*2)*(-2,1)=10*(-2,1)=-21$