Question 324183
Calculate both of the slopes.
{{{m1=(y2-y1)/(x2-x1)=(8-(-3))/(-7-3)=-(11/10)}}}
{{{m2=(7-(-3))/(3-(-8))=10/11}}}
Perpendicular lines have slopes that are negative reciprocals,
{{{m1*m2=-1}}}
{{{-(11/10)(10/11)=-1}}}
{{{-1=-1}}}
True, so therefore the lines are perpendicular.
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{{{drawing(300,300,-10,10,-10,10,grid(1),circle(3,-3,.3),circle(-7,8,.3),circle(-8,-3,.3),circle(3,7,.3),line(3,-3,-7,8),line(-8,-3,3,7),graph(300,300,-10,10,-10,10,0))}}}