Question

Sheila plans to row across the lake from point A to point B as shown below.

Answer 1

Answer: 15.58 miles

Step-by-step explanation:

Given two sides and an included angle, segment AB can be calculated using the cosine rule :

Given a = 15.6 miles, b = 12.3 miles and C=α=66.7°

To find c:

c= √(a^2+b^2-2abcosα

c = √ 15.6^2 + 12.3^2 -(2 × 15.6 × 12.3)cos66.7°

c = √243.36 + 151.29 - 151.79454

c = √242.85545

c = 15.583820

c = 15.58 miles