INSTRUCTORSCarleen EatonGrant Fraser

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Distance Formula

  • The Distance formula asserts that the distance between the points (x1, y1) and (x2, y2) in the coordinate plane is √(x2 – x1)2 + (y2 – y1)2. This formula is a special case of the Pythagorean theorem.

  • Make sure that you know and understand how to use this formula. It will be used in a lot of later work.

  • In the Distance formula, the order of the x coordinates does not matter. So take whichever difference is easier to compute. The same comment applies to the y coordinates.

  • After squaring the differences in the distance formula, be sure to take the positive square root of their sum.

  • In some problems, you are given the distance between two points and three of their coordinates. In this situation, use the Distance formula to find the fourth coordinate.

Distance Formula

Lecture Slides are screen-captured images of important points in the lecture. Students can download and print out these lecture slide images to do practice problems as well as take notes while watching the lecture.

Mathematics: Algebra 1