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    Geometry & TrigonometryHard

    Right triangles and trigonometry

    Use the Pythagorean theorem and SOH-CAH-TOA to find missing sides and angles in right triangles.

    Sample SAT Problem

    In a right triangle, the legs are 5 and 12. What is the hypotenuse?

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    Step-by-Step Solution

    c = √(5² + 12²) = √(25 + 144) = √169 = 13.

    Key Tips from Pamela

    • SOH: sin = opposite/hypotenuse. CAH: cos = adjacent/hypotenuse. TOA: tan = opposite/adjacent.
    • Common Pythagorean triples: 3-4-5, 5-12-13, 8-15-17.
    • sin(θ) = cos(90° − θ) — use this for complementary angle problems.

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