Question

The equation of the line passing through the point (1, 2) and perpendicular to the line $x + y + 1 = 0$ is.

• A. $y - x + 1 = 0$
• B. $y - x - 1 = 0$
• C. $y - x + 2 = 0$
• D. $y - x - 2 = 0$

Answer 1

Answer: (B)

$y - x - 1 = 0$

Answer 2

The line perpendicular to the line $x + y + 1 = 0$ is $y - x + \lambda = 0$. Also, it passes through the point (1, 2);

$\therefore$ $\lambda = - 1$ . Hence, required line is $y - x - 1 = 0$.