The Distance Formula
The Distance Formula is a variant of the Pythagorean Theorem.
Suppose you're given the two points (–2, 1) and (1, 5), and they want you to find out how far apart they are. The points look like this: |
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You can draw in the lines that form a right-angled triangle, using these points as two of the corners: |
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It's easy to find the lengths of the horizontal and vertical sides of the right triangle: just subtract the x-values and the y-values: |
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Then use the Pythagorean Theorem to find the length of the third side (which is the hypotenuse of the right triangle):
c2 = a2 + b2
then... Copyright © Elizabeth Stapel 2000-2011 All Rights Reserve
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