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Cool Math

Coolmath: Perpendicular Lines

For Students 9th - 10th Standards
This CoolMath Resource will help students determine if lines are perpendicular by finding the slope, using the point-slope formula, and graphing.
Handout
Purple Math

Purplemath: Using Slope and Y Intercept to Graph Lines

For Students 6th - 8th
Demonstrates, step-by-step and with illustrations, how to use slope and the y-intercept to graph straight lines.