Angles by cosine law

Calculate the size of the angles of the triangle ABC, if it is given by: a = 3 cm; b = 5 cm; c = 7 cm (use the sine and cosine theorem).

Result

A =  21.787 °
B =  38.213 °
C =  120 °

Solution:

Solution in text A =

Try calculation via our triangle calculator.

Solution in text B =
Solution in text C =







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Pythagorean theorem is the base for the right triangle calculator. See also our trigonometric triangle calculator. Try conversion angle units angle degrees, minutes, seconds, radians, grads. Cosine rule uses trigonometric SAS triangle calculator.

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