+5265 It depends on the triangle.
45-45-90 both legs equal each other while the hypotenuse equals the leg times the square root of 2.
30-60-90 The vertical leg equals the base leg's length times the square root of 3, while the hypotenuse equals 2 times the base leg.
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+5265 Otherwise, use the Pythagorean Theorem:
\(\sqrt{a^2+b^2}=c\)
Think of the radical symbol like parentheses, do everything inside of it first.
