Выполните делениеномер 1198

1) [latex] \frac{5x-3}{2}: \frac{3-5x}{7}= \frac{5x-3}{2} * \frac{7}{3-5x}= \frac{(5x-3)*7}{2(3-5x)}= \frac{(5x-3)*7}{2(-(-3+5x))}=- \frac{(5x-3)*7}{2(-3+5x)}= [/latex] [latex]= -\frac{(5x-3)*7}{2(5x-3)}=- \frac{7}{2}=-3 \frac{1}{2} [/latex] 2) Сразу перевернул... [latex] \frac{9y-2}{5}* \frac{3}{2-9y}= \frac{(9y-2)*3}{5(2-9y)}=- \frac{(9y-2)*3}{5(9y-2)}=- \frac{3}{5} [/latex] 3) [latex] \frac{7-x}{6} * \frac{9}{x-7}= \frac{7-x}{2} * \frac{3}{x-7}= \frac{(7-x)*3}{2(x-7)}= -\frac{(x-7)*3}{2(x-7)}=- \frac{3}{2}=-1 \frac{1}{2} [/latex] 4) [latex] \frac{12-ab}{5} * \frac{6}{ab-12}= \frac{(12-ab)*6}{5(ab-12)}=- \frac{(ab-12)*6}{5(ab-12)}=- \frac{6}{5}=-1 \frac{1}{5} [/latex]