Question

A line passes through the point (12,–4) and is perpendicular to the line with the equation y = 6x + 3. What's the equation of the line?

Answer 1

I'm just gonna so you how I got it

Explanation:

6x - 3y - 5 = 0 has slope 6/3 = 2. A perpendicular line will have slope -1/2 (since slopes of two perpendicular lines must have a product of -1), so its general form will be 3x + 6y - a = 0.

Now to find a. We know a point on the line, (4,10), and so we plug those coordinates in:

3*4 + 6*10 - a = 0

12 + 60 - a = 0

72 = a

3x + 6y - 72 = 0.

We can simplify this by dividing all numbers by 3, getting:

x + 2y - 24 = 0