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A line is perpendicular to (3x – y + 11 = 0) and passes through…

A line is perpendicular to (3x – y + 11 = 0) and passes through the point (1, -5). Find its equation.

  • A.
    3y – x -14 = 0
  • B.
    3x + y + 1 = 0
  • C.
    3y + x + 1 = 0
  • D.
    3y + x + 14 = 0
Correct Answer: Option D
Explanation

(3x – y + 11 = 0 implies y = 3x + 11)

(Gradient = 3)

Gradient of perpendicular line = (frac{-1}{3})

(therefore frac{y – (-5)}{x – 1} = frac{-1}{3})

(3(y + 5) = 1 – x)

(3y + x + 15 – 1 = 3y + x + 14 = 0)