Question

Find the missing parts of the triangle. Round to the nearest tenth when necessary or to the nearest minute as appropriate.

a = 7.3 in.
b = 13.2 in.
c = 15.8 in.

A = 27.3°, B = 56.1°, C = 96.6°
No triangle satisfies the given conditions.
A = 29.3°, B = 54.1°, C = 96.6°
A = 25.3°, B = 56.1°, C = 98.6°

Answer 1

• A) A = 27.3°, B = 56.1°, C = 96.6°

Explanation:

Use the Law of Cosines:

• A = arccos [(b² + c² - a²)/(2bc)] = arccos [(13.2² + 15.8² - 7.3²)/(2*13.2*15.8)] = 27.3°
• B = arccos [(a² + c² - b²)/(2ac)] = arccos [(7.3² + 15.8² - 13.2²)/(2*7.3*15.8)] = 56.1°
• C = 180° - (A + B) = 180° - (27.3° + 56.1°) = 96.6°

Correct choice is A.