# 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).

A =  21.7868 °
B =  38.2132 °
C =  120 °

### Step-by-step explanation:

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$C=180-A-B=180-21.7868-38.2132=120\text{°}$ Did you find an error or inaccuracy? Feel free to write us. Thank you! Tips to related online calculators
Cosine rule uses trigonometric SAS triangle calculator.
Pythagorean theorem is the base for the right triangle calculator.

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