So what's the purpose of all these FORMS, anyway?

Standard Form?        Ax + By = C

Point-Slope Form?       y₂- y₁ = m(x₂ - x₁)

Slope-Intercept Form?          y = mx + b

It's enough to drive a body CRAZY!!  How do you know when to use which?

Try using these guidelines...

If you're handed a point and the slope of a line…	Use Point-Slope Form
If you're handed two points….	Use the two points to find the slope; then use Point-Slope Form
If you're handed the slope and the y-intercept…	Use Slope-Intercept Form
If you're trying to study the graph of a line…	Use Slope-Intercept Form
If a point is known, and the line is parallel to another…	Find the slope of the known line; then use Point-Slope Form
If a point is known, and the line is perpendicular to another…	Find the slope of the known line; then use its negative reciprocal in Point-Slope Form
To reconcile different forms…	Transform into Standard Form

Take me back to the Fast Facts Directory.

On Line Math Learning Center Home Page.