Question

50x²y-70x²y²+20xy² при x=0,2, y=-1,5

Answer 1

$\displaystyle\bf\\50x^{2} y-70x^{2} y^{2}+20xy^{2} =10xy(5x-7xy+2y)\\\\\\x=0,2 \ ; \ y=-1,5\\\\\\10xy(5x-7xy+2y)=10\cdot 0,2\cdot (-1,5)\cdot\Big(5\cdot 0,2-7\cdot 0,2\cdot (-1,5)+2\cdot(-1,5)\Big)=\\\\\\=-3\cdot(1+2,1-3)=-3\cdot0,1=-0,3$