Question

Решите примеры пожалуйста.

Answer 1

1)
$\frac{ {2}^{2} - {0.8}^{2} }{2.8 \times 0.4 - 2.8 \times 1.4} = \frac{4 - 0.64}{ - 1 \times 2.8} = \\ = \frac{3.36}{ - 2.8} = - 1.2$
2)
$\frac{ {3.5}^{2} - {2.5}^{2} }{0.8 \times 0.6 - 0.6} = \frac{12.25 - 6.25}{0.48 - 0.6} = \\ = \frac{6}{ - 0.12} = - 50$
3)
$\frac{1.6 \times 0.4 - 0.4}{ {1.4}^{2} - {2.6}^{2} } = \frac{0.64 - 0.4}{1.96 - 6.76} = \\ = \frac{0.24}{ - 4.8} = - 0.05$

Answer 2

$\displaystyle 28)..\frac{2^{2}-0,8^{2}}{2,8*0,4-2,8*1,4}= \frac{(2-0,8)(2+0,8)}{2,8*(0,4-1,4)}= -\frac{1,2*2,8}{2,8}=-1,2 \\ \\ \\ 29).. \frac{3,5^{2}-2,5^{2}}{0,8*0,6-0,6}= \frac{(3,5-2,5)(3,5+2,5)}{0,6*(0,8-1)}= -\frac{6}{0,6*0,2}=-50 \\ \\ \\ 30).. \frac{1,6*0,4-0,4}{1,4^{2}-2,6^{2}}= \frac{0,4*(1,6-1)}{(1,4-2,6)(1,4+2,6)}= -\frac{0,4*0,6}{1,2*4}= \\ \\ = -\frac{24}{480}= -\frac{1}{20}=-0,05$