1 Answers
Option 2 : 3x + y - 23 = 0
As per the given data, we get
x - y - 5 = 0 ….. (1)
x - 3y - 1 = 0 ….. (2)
Solving equation (1) and equation (2), we get
⇒ x = 7 and y = 2
∴ Point of intersection of the lines x - y - 5 = 0 and x - 3y - 1 = 0 is (7, 2)
We know that,
Slope of line ax + by + c = 0 is –a/b
⇒ Slope of the line x - 3y + 21 = 0 is - 1/(-3) = 1/3
We know that,
Product of slopes of two perpendicular lines = -1
∴ Required slope of the line = -3
Hence, the required line passes through the point (7, 2) and has a slope of -3.
We know that,
Point - slope form of a line through the point (x1, y1) and slope ‘m’ is (y - y1) = m(x - x1)
Line passing through (7, 2) and with slope (-3) is
⇒ (y - y1) = m (x - x1)
⇒ (y - 2) = -3(x - 7)
⇒ y - 2 = -3x + 21
⇒ 3x + y - 23 = 0
∴ Required line is 3x + y - 23 = 0