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SOMEONE PLEASE HELP ASAP!!!! Solve the triangle round to the nearest tenth.

SOMEONE PLEASE HELP ASAP!!!! Solve the triangle round to the nearest tenth.-example-1

1 Answer

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Answer:

s = 13.6

m∠T = 35.7°

m∠U = 61.3°

Explanation:

• Solving for side s:

To find the length of side s, we have to use the cosine rule:


\boxed{a^2 = b^2 + c^2 - 2bc \ cosA},

where:

  • a = unknown side
  • b, c = adjacent sides
  • A = angle opposite to the unknown side.

In this case, the unknown side is s, and the sides adjacent to it have lengths of 8 and 2. The angle opposite to s is ∠S = 83°. Therefore,


s^2 = 8^2 + 12^2 -2(8)(12) \cdot cos(83^(\circ))


s = \sqrt{8^2 + 12^2 -2(8)(12)\cdot cos(83^(\circ))}


s = \bf 13.6

• Solving for m∠T:

In order to find m∠T, we can use the sine rule:


\boxed{(sinA)/(a)= (sinB)/(b) =(sinC)/(c)},

which means that the ratios of the sines of angles and their opposite sides are equal for a triangle.

The side opposite to ∠T is US = 8. Therefore:


{(sinT)/(8) = (sin(83^(\circ)))/(13.6)}


sinT= (sin(83^(\circ)))/(13.6) * 8


T = sin^(-1)( (sin(83^(\circ)))/(13.6) * 8)


T = \bf 35.7^(\circ)

• Solving for m∠U:

Now that we know the values of two angles of the triangle, we can calculate the third angle using the fact that the angles in a triangle add up to 180°:

U + ∠S T = 180°

⇒ ∠U + 83° + 35.7° = 180°

⇒ ∠U = 180° - 83° - 35.7°

⇒ ∠U = 61.3°

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