Line has equation . Line is perpendicular to and passes through . Where does cross the -axis?

Answer and explanation

Correct answer: B.

  1. Step 1: Perpendicular gradient: .
  2. Step 2: : , so .
  3. Step 3: At , .
Answer
.
Why not the others: : uses the gradient instead of the perpendicular gradient. : uses the gradient , forgetting to make it negative. : uses the gradient , which is negative but not the reciprocal.

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