# How do you find equation of a line, L which passes through the point (3, -1) and perpendicular to the line with equation 9x - 3y = 2?

##### 1 Answer

#### Explanation:

To solve this we must first determine the slope of the given line by converting the equation to the slope-intercept form which is:

So the slope of the given line is

The slope of a perpendicular line is the negative inverse of the line give. So if

So, in this case the slope of the perpendicular line is

We now have a slope and a point so we can use the point-slope to determine the equation for the perpendicular line.

The point-slope formula states:

Where

Substituting the information we were given and calculated gives:

#y + 1 = -1/3x + 1/3 * 3

or converting to the more familiar point-intercept form gives: