Khan Academy: More Analytic Geometry: Parallel Lines 3

Can you prove it? Making assumptions in geometry is commonplace. This resource requires mathematicians to prove the parallel line postulate through constructions. Learners construct parallel lines with a 180-degree rotation and then...

This resource explores parallel lines and requires students to practice calculations and analyze angles. By asking viewers to decide whether two lines are parallel based on the information given, this second part of the parallel lines...

Providing an exploration of parallel lines, this resource requires students to not only practice calculations, but also to analyze angles. By asking viewers to decide whether two lines are parallel based upon the information given, this...

Segment transversals proportionally. Given a diagram with three parallel lines and two transversals, the narrator of a short video points out the parallel lines cut the transversals proportionally. The portion of a long playlist on...

Here is a fairly basic video that uses three equations, each written in slope-intercept form, to determine whether the lines are parallel. Sal graphs each equation on the same coordinate plane to show how their slopes compare. The video...

Can you tell, algebraically, if three lines are parallel? In this video, Sal demonstrates how to rewrite linear equations in slope-intercept form and compare the slope of each line.

The video tutorial investigates parallel lines.

The video tutorial investigates parallel lines.

This video demonstrates how to find the equation of a line when given a point on the line and the equation of a line perpendicular to it.

Parallel lines must always have the same slope. Learners use this bit of information to extend their equation writing skills. A video lesson explains how to write the equation of a line parallel to a given line and through a given point....