Question

Check the position of points (1, 2) and (−5, −1) with respect to the line x + y + 2 + 0. 

Answer 1

Using the inequality (ax₁ + by₁ + c)·(ax₂ + by₂ + c) > 0 or < 0, we can say the point lies on the same side and the opposite side of the line.

(1 + 2 + 2)·(−5 − 1 + 2) < 0

Hence, the points lie on the opposite sides of the given line.