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Law of Cosines to find the remaining side(s) and angle(s) if possible. a = 60.12mi, b = 40.23 mi, Cγ = 48.7°

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Remaining side (c): 45.17 miles

Remaining angle A: 42.0 degrees

Remaining angle B: 89.3 degrees

Solving for the Remaining Side and Angle in a Triangle

Given:

Triangle with sides:

a = 60.12 miles

b = 40.23 miles

Angle C (γ) = 48.7°

To find:

Remaining side (c)

Remaining angles (A and B)

Using the Law of Cosines:

The Law of Cosines states that for any triangle ΔABC with sides a, b, and c, and angle C opposite side c:

c² = a² + b² - 2ab * cos(C)

Finding side c:

Convert angle C to radians: C_rad = 48.7° * π/180° ≈ 0.8506 radians

Substitute known values: c² = 60.12² + 40.23² - 2 * 60.12 * 40.23 * cos(0.8506)

Solve for c: c ≈ 45.17 miles

Finding angle A:

Use the Law of Sines:

sin(A) / a = sin(C) / c

Substitute values: sin(A) / 60.12 = sin(0.8506) / 45.17

Solve for A: A ≈ 42.0 degrees

Finding angle B:

Use the Law of Sines:

sin(B) / b = sin(C) / c

Substitute values: sin(B) / 40.23 = sin(0.8506) / 45.17

Solve for B: B ≈ 89.3 degrees

User Ben Cheng
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