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100 Points! Geometry question. Photo attached. Please show as much work as possible. Thank you!

100 Points! Geometry question. Photo attached. Please show as much work as possible-example-1

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Answer:

Answers following the rounding instructions: see below for details

BC = 5.1

m∠B = 23°

m∠V = 116°

Explanation:

Givens:

AC = 3

AB = 7

m∠A = 41°

Unknowns:

BC = ?

m∠B = ?

m∠C = ?

Find side BC using the law of cosines: c² = a² + b² - 2ab cos(C)

a² = 3² + 7² - 2(3)(7)(cos41)

a = √9 + 49 - 42(cos41)

a = 5.128 ≈ 5.13

side BC = 5.13

Use the law of sines to find m∠B: sin(A) / a = sin(B) / b = sin(C) / c

m∠B = sin⁻¹[sin41/5.13 x 3] = sin⁻¹(0.3837) = 22.56 ≈ 22.6°

Sum of interior angles of a triangle is 180, so now you can find m∠C:

m∠C = 180 - 22.6 - 41 = 116.44 ≈ 116.4°

Rounding side BC to nearest tenth: BC = 5.1

Rounding angles to nearest whole degree:

m∠B = 23°

m∠V = 116°

User Nyphur
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