In triangle ABC: angle C = 90 degrees; BC = 12; ab = 1 cubed. Find tg angle A.

1. By the Pythagorean theorem, in the triangle ABC we find AC

AB ^ 2 = BC ^ 2 + AC ^ 2

1 = 144 + AC ^ 2

AC ^ 2 = 144 – 1

AC ^ 2 = 143

AC = √ 143

2. The tangent of the angle is the ratio of the opposite leg to the adjacent leg.
Adjacent leg AC = √ 143

Opposite leg BC = 12

Find tgA.

tgA = 12 / √143

Answer: 12 / √143

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