Question 894638
The product of the slopes must be {{{-1}}}.


{{{((-3-2)/(2-(-4)))((5-(-1))/(a-2))=-1}}}
{{{(5/2)(6/(a-2))=-1}}}
{{{(5*6)=-1*(2(a-2))}}}
{{{30=-2(a-2)}}}
{{{-15=a-2}}}
{{{a=-15+2}}}
{{{highlight(a=-13)}}}