Welcome to Westonci.ca, where your questions are met with accurate answers from a community of experts and enthusiasts. Join our Q&A platform to get precise answers from experts in diverse fields and enhance your understanding. Connect with a community of professionals ready to help you find accurate solutions to your questions quickly and efficiently.
Sagot :
Answer:
AB or the distance across the river is about 171.36 meters.
Step-by-step explanation:
Please refer to the diagram below (not to scale). The area between the two blue lines is the river.
To find AB, we can use the Law of Sines. Recall that:
[tex]\displaystyle \frac{\sin A}{a} = \frac{\sin B}{b} = \frac{\sin C}{c}[/tex]
BC (or a) is opposite to ∠A and AB (or c) is opposite to ∠C. Thus, we will substitute in these values.
First, find ∠A. The interior angles of a triangle must total 180°. Thus:
[tex]m\angle A + m\angle B + m\angle C = 180^\circ[/tex]
Substitute:
[tex]\displaystyle m\angle A + (112.2^\circ) +(18.3^\circ) = 180^\circ[/tex]
Solve for ∠A:
[tex]m\angle A = 49.5^\circ[/tex]
Substitute BC for a, AB for c, 49.5° for A and 18.3° for C into the Law of Sines. Thus:
[tex]\displaystyle \frac{\sin 49.5^\circ}{BC} = \frac{\sin 18.3^\circ}{AB}[/tex]
Since BC = 415 m:
[tex]\displaystyle \frac{\sin 49.5^\circ}{415} = \frac{\sin 18.3^\circ}{AB}[/tex]
Solve for AB. Cross-multiply:
[tex]\displaystyle AB \sin 49.5^\circ = 415\sin 18.3^\circ[/tex]
And divide:
[tex]\displaystyle AB = \frac{415\sin 18.3^\circ}{\sin 49.5^\circ}[/tex]
Use a calculator. Hence:
[tex]AB = 171.3648...\approx 171.36\text{ m}[/tex]
AB or the distance across the river is about 171.36 meters.

We hope this information was helpful. Feel free to return anytime for more answers to your questions and concerns. We appreciate your visit. Our platform is always here to offer accurate and reliable answers. Return anytime. Thank you for choosing Westonci.ca as your information source. We look forward to your next visit.