Question 1079964
Slope of line containing  (4,4) & (-2,1):
{{{(4-1)/(4-(-2))}}}
{{{3/6}}}
{{{1/2}}}



Slope of line containing  (-1,y) & (1,0), to be perpendicular, must be {{{-2}}}, negative reciprocal of the other line.



{{{(y-0)/(-1-1)=-2}}}


{{{y/(-2)=-2}}}


{{{highlight(y=4)}}}