Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: from C to the island. Using Theorem 10.4, we get sin (45◦ ) = y . After some rearranging, d √ we find y = d sin (45◦ ) ≈ 9.66 22 ≈ 6.83 miles. Hence, the island is approximately 6.83 miles from the coast. To find the distance from Q to C , we note that β = 180◦ − 90◦ − 45◦ = 45◦ so by symmetry,11 we get x = y ≈ 6.83 miles. Hence, the point on the shore closest to the island is approximately 6.83 miles down the coast from the second observation point. Sasquatch Island Sasquatch Island β β d ≈ 9.66 miles 30◦ γ 45◦ Q P d ≈ 9.66 miles y miles 45◦ Shoreline Q 5 miles C x miles We close this section with a new formula to compute the area enclosed by a triangle. Its proof uses the same cases and diagrams as the proof of the Law of Sines and is left as an exercise. Theorem 11.4. Suppose (α, a), (β, b) and (γ, c) are the angle-side opposite pairs of a triangle. Then the area A enclosed by the triangle is given by 1 1 1 A = bc sin(α) = ac sin(β ) = ab sin(γ ) 2 2 2 Example 11.2.4. Find the area of the triangle in Example 11.2.2 number 1. Solution. From our work in Example 11.2.2 number...
View Full Document

This note was uploaded on 05/03/2013 for the course MATH Algebra taught by Professor Wong during the Fall '13 term at Chicago Academy High School.

Ask a homework question - tutors are online