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
01Find every side of a 30-60-90 triangle from its short legFind the short leg across from the 30-degree angle, then multiply it by the square root of 3 for the long leg and by 2 for the hypotenuse.
02Find the hypotenuse of a 45-45-90 triangle from one legMultiply one leg by the square root of 2 to get the hypotenuse.
03Give an exact square root or a decimal to match the answer choicesKeep the square root in your answer when the choices show square roots, and type it into Desmos only when the choices are decimals.
This lesson is part of the full library
207 lessons that teach every skill the SAT tests
71Math
40Reading
24Grammar
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