In this video, Sal Khan demonstrates how to know which lines are perpendicular when solving an algebraic equation. (The instructor tells and demonstrates what perpendicular lines are.) Mr. Khan uses the Paint Program (with different colors) to illust...rate his points. Sal Khan is the recipient of the 2009 Microsoft Tech Award in Education. (03:28) There is a lot of information on the screen--the viewer may want to open the video to 'full screen.'[more]

Perpendicular lines are lines that intersect each other at right angles. In this video, Sal Khan demonstrates how to know which lines are perpendicular when solving an algebraic equation. Mr. Khan uses the Paint Program (with different colors) to ill...ustrate his points. Sal Khan is the recipient of the 2009 Microsoft Tech Award in Education. (03:28) There is a lot of information on the screen--the viewer may want to open the video to 'full screen.'[more]

Second part of determining the slope of a line. This video starts off with a black screen because the narrator uses it as a 'chalkboard'. This video is appropriate for older mddle and high school students.

In this video, Sal Khan demonstrates how to know which lines are parallel when solving an algebraic equation. Mr. Khan uses the Paint Program (with different colors) to illustrate his points. Sal Khan is the recipient of the 2009 Microsoft Tech Award... in Education. (02:42) There is a lot of information on the screen--the viewer may want to open the video to 'full screen.'[more]

In this video, Sal Khan demonstrates how to know which lines are parallel when solving an algebraic equation. Mr. Khan uses the Paint Program (with different colors) to illustrate his points. Sal Khan is the recipient of the 2009 Microsoft Tech Award... in Education. (03:48) There is a lot of information on the screen--the viewer may want to open the video to 'full screen.'[more]

In this video, Sal Khan demonstrates how to know which lines are parallel when solving an algebraic equation. Mr. Khan uses the Paint Program (with different colors) to illustrate his points. Sal Khan is the recipient of the 2009 Microsoft Tech Award... in Education. (03:48) There is a lot of information on the screen--the viewer may want to open the video to 'full screen.'[more]

Third part of determining the slope of a line. This video starts off with a black screen because the narrator uses it as a 'chalkboard'. This video is appropriate for older mddle and high school students.

Figuring out the slope of a line. This video starts off with a black screen because the narrator uses it as a 'chalkboard'. This video is appropriate for high school students.

In this video clip, the instructor uses an electronic chalkboard to demonstrate how to write the equation of a line when given two points. Two examples are modeled. (06:45)

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