Write a slope-intercept equation for the line shown:

The line crosses the y-axis at (0, -1). That's our b, -1. We will call her Larry, the Attack b. She will make us honey and sting our enemies.

Starting from Larry, we can follow the line and see that it rises by 2 and runs by -1. Or it rises by -2 and runs by 1, either way. That gives us a slope of m = -2.

Now just use the formula for slope-intercept form, y = mx + b, to write the equation.

y = -2x – 1

Write an equation of the line that passes through (4, 3) and is perpendicular to the line y = 2x + 1.

When two lines are perpendicular, their slopes are the negative reciprocal of each other. That's right, they're both the evil twin; they're even sporting matching goatees. This means the slope of the line we're looking for is:

We have a point and a slope, so we're going to use the hopscotch method of finding the equation of a line. Well, only if the point-slope method doesn't work.

Guess we won't be playing hopscotch today. *sigh*

Write an equation of the line that passes through (6, 3) and (0, 2).

We need the two-points method here. The steps to this dance are the usual: get the slope, pick a point, plug it into the point-slope method, and then simplify.

With the slope in hand, the music picks up. Grab your partner point and do-si-do.

With a spin and a flourish, we're done. However, we have an encore. The point (0, 2) is actually the y-intercept, b = 2. Once we had the slope, we could have finished the problem immediately.