Question -
Answer -
Given (1, -5), (-4, 5)and (λ, 7) are collinear
We have the conditionthat three points to be collinear, the area of the triangle formed by thesepoints will be zero. Now, we know that, vertices of a triangle are (x1,y1), (x2, y2) and (x3, y3),then the area of the triangle is given by,
⇒ – 50 – 10λ = 0
⇒ λ = – 5