# 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).

### Correct answer:

Tips to related online calculators

Cosine rule uses trigonometric SAS triangle calculator.

See also our trigonometric triangle calculator.

Pythagorean theorem is the base for the right triangle calculator.

See also our trigonometric triangle calculator.

Pythagorean theorem is the base for the right triangle calculator.

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