Question

By using slope method, show that the points P(4, 8), Q(5, 12) and R(9, 28) are collinear.

Answer 1

The given points are P(x₁ y₁) = (4, 8), 

Q(x_2, y₂) = (5, 12) and R(x₃,y₃) = (9, 28). 

∴ Slope of line PQ, m₁ = \(\frac{12-8}{5-4}=4\)

And Slope of line PR, m₂ = \(\frac{28-8}{9-4}=4\)

Since, slope of PQ = Slope of PR. 

∴ The points P, Q and R are collinear