$K=2x(-3x+5)+3x(2x-12)+26x$
$=-6x^{2}+10x+6x^{2}-36x+26x$
$=(-6x^{2}+6x^{2})+(10x-36x+26x)$
$=0x$
$=0$
$M=\frac{-2x}{3}+3x(\frac{x}{6}-\frac{-2}{9}-\frac{7}{5})-\frac{5x}{2}(\frac{x}{5}-\frac{4}{5})$
$=\frac{-60}{90}+3x(\frac{15x}{90}-\frac{-20}{90}-\frac{126}{90})-\frac{225}{90}(\frac{18}{90}- \frac{72}{90})$
$=\frac{-60}{90}+3x.\frac{15x+20-126}{90}-\frac{225}{90}.(-\frac{3}{5})$
$=\frac{-60}{90}+3x.\frac{15x-106}{90}+\frac{3}{2}$
$=\frac{-60}{90}+\frac{x(15x-106)}{30}+\frac{3}{2}$
$=\frac{5}{6}+\frac{x(15x-106)}{30}$
$=\frac{25+15x^{2}-106x}{30}$