Question

Check whether the point (−4, 3) lies on both the lines represented by the linear equations x + y + 1 = 0 and x − y = 1.

Answer 1

Given the equations of line are

⇒ x + y = −1    ...(i)

⇒ x − y = 1    ...(ii)

The intersection point of both the lines will be the point that lies on both the lines,

So, adding eqn (i) and (ii),

⇒ (x + y) + (x − y) = −1 + 1

⇒ 2x = 0

⇒ x = 0

Putting in eqn (i),

⇒ 0 + y = −1

⇒ y = −1

So, the point will be (x, y) = (0, −1)

Hence, the point (−4, 3) does not lie on both the lines.