Question

The area of triangle PQR is 6sq. Units . If P(x,y) , Q(1,2) , R(2,1) , then prove that x+y-15=0 or x+y+9=0

Answer 1

Here ,

Area of triangle =

1/2 * {x1(y2-y3)+x2(y3-y1)+x3(y1-y2)}

$\underline{\mathfrak{\huge{Thank You}}}$