Geometry and Trigonometry practice question

Answer: 45

sin θ = opposite/hypotenuse and cos θ = adjacent/hypotenuse. They are equal when opposite = adjacent, which makes the triangle isosceles with acute angles of 45° each.

Common wrong answers

If you answered 30

At 30°, sin = 1/2 and cos = √3/2, which differ.

If you answered 60

At 60°, sin = √3/2 and cos = 1/2, which differ.

If you answered 90

At 90°, sin is 1 and cos is 0 — not equal, and 90° isn't acute.

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