Question

The lengths of three sides of a triangle are 10 centimeters, 11 centimeters, and 13 centimeters. Find the measure of the smallest angle of the triangle.

Answer 1

Answer:

• 48.4°

Step-by-step explanation:

The smallest angle is opposite to the smallest side.

Use the law of cosines to find the angle opposite to side with the length of 10 cm:

• cos A = (b² + c² - a²)/(2bc)

• cos x = (11² + 13² - 10²)/(2*11*13)
• cos x = 190/286
• cos x = 0.664 (rounded)
• x = arccos (0.664)
• x = 48.4° (rounded)