Question

Помогите ришить всё первый решил сам дальшэ незнаю

Answer 1

$\frac{6.8-4.7}{1.4} =\frac{2.1}{1.4} =\frac{0.3}{0.2} =\frac{3}{2}$

$(\frac{13}{30} -\frac{11}{20} )*\frac{9}{5} =(\frac{26}{60} -\frac{33}{60} )*\frac{9}{5} =-\frac{7}{60} *\frac{9}{5} =-\frac{63}{300} =-\frac{21}{100} =-0.21$

$\frac{6ab}{ab-4a^{2}} =\frac{6ab}{a(b-4a)} =\frac{6b}{b-4a}$

$\frac{5b^{2}}{a^{2}-49b^{2}} :\frac{b}{a^{2}+7ab} =\frac{5b^{2}}{(a-7b)(a+7b)}:\frac{b}{a(a+7b)} =\frac{5b^{2}}{(a-7b)(a+7b)}*\frac{a(a+7b)}{b} =\frac{5ab}{a-7b}$

$\frac{1}{6x} -\frac{6x+y}{6xy} =\frac{y}{6xy} -\frac{6x+y}{6xy} =\frac{y-6x-y}{6xy} =-\frac{6x}{6xy} =-\frac{1}{y}$