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
Solution:
B. y – x – 1 = 0
Explanation:
Given that line passing through the point (1, 2)
And perpendicular to the line x + y + 1 = 0
Let the equation of line ‘L’ is
x – y + k = 0 … (i)
Since, L is passing through the point (1, 2)
∴ 1 – 2 + k = 0
⇒ k = 1
Putting the value of k in equation (i), we get
x – y + 1 = 0
Or y – x – 1 = 0
Hence, the correct option is (b)