Pythagorean theoremThe rule that in a right triangle, the squares of the two shorter sides add up to the square of the longest side: a² + b² = c².
You’ll leave with these skills
01Spot the hypotenuse of a right triangleFind the side across from the small square that marks the right angle, and use it as the hypotenuse in the equation.
02Recognize whole-number right triangles such as 3-4-5 and their multiplesCheck whether the two known sides fit a 3-4-5,5-12-13,8-15-17, or 7-24-25 triangle or a multiple of one, and read off the third side.
03Find the right triangle hidden in a rectangle, a ladder, or a graphFind the two sides that meet at a right angle in the picture or story, and use them as the legs of a right triangle.
04Find a missing leg of a right triangleSubtract the known leg’s square from the hypotenuse’s square, then take the square root.
This lesson is part of the full library
207 lessons that teach every skill the SAT tests
71Math
40Reading
24Grammar
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