Помогите!!!!!!!!!!!!!!!

1) $\frac{y+2xy}{x^2-y}|_{x=0,y=-1}= \frac{-1+2*0*(-1)}{0^2-(-1)}=\frac{-1}{1}=-1$

2) $\frac{a}{a+2b},and,\frac{-2b}{2b-a}$

$\frac{a}{a+2b}* \frac{a-2b}{a-2b},and,\frac{2b}{-(2b-a)}*\frac{a+2b}{a+2b}$

$\frac{a(a-2b)}{(a+2b)(a-2b)},and,\frac{2b(a+2b)}{-(2b-a)(a+2b)}$

$\frac{a(a-2b)}{(a+2b)(a-2b)},and,\frac{2b(a+2b)}{(a-2b)(a+2b)}$

3) $2\frac{1}{4}a^{-1}b^3*(\frac{2}{9}a^2b^{-3})= \frac{2*4+1}{4}* \frac{2}{9}*a^{-1}*a^2*b^3*b^{-3}=$

$=\frac{9}{4}* \frac{2}{9}*a^{-1+2}*b^{3+(-3)}=\frac{2}{4}*a^1*b^0=0.5a=\frac{a}{2}$

4) $\frac{2x}{3}:\frac{3}{2x}*\frac{9}{4xy}:\frac{x}{2y}=(\frac{2x}{3}:\frac{3}{2x})*\frac{9}{4xy}:\frac{x}{2y}=(\frac{2x}{3}*\frac{2x}{3})*\frac{9}{4xy}:\frac{x}{2y}=$

$=\frac{2x*2x*9}{3*3*4xy}:\frac{x}{2y}=\frac{4x^2*9}{9*4xy}*\frac{2y}{x}=\frac{4x^2}{4xy}*\frac{2y}{x}=\frac{4x^2y*2}{4x^2y}=2$

5) $\frac{1-x}{2}+\frac{2+3x}{5}+\frac{x}{6}=\frac{1}{30}$

$\frac{(1-x)*15}{2*15}+\frac{(2+3x)*6}{5*6}+\frac{x*5}{6*5}=\frac{1}{30}$

$15(1-x)+6(2+3x)+5x=1$

$15-15x+12+18x+5x=1$

$8x=-26$

$2*4x=2*13$

$4x=13$

$x=\frac{13}{4}$