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In triangle PQR; m angle R is 90, m angle PQR is 75, M belongs to PR, MP is 18, m angle MQR is 60. Find RQ

User Xyphoid
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1 Answer

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The length of segment RQ in triangle PQR is approximately 82.45 units.

Finding RQ in Triangle PQR

Here's how to find RQ step-by-step:

1. Analyze the given information:

Triangle PQR is a right triangle with angle R = 90°.

Angle PQR measures 75°.

Point M lies on line segment PR, and MP = 18.

Angle MQR measures 60°.

2. Find angle QMP:

Using the angle sum property of triangles in PQR:

∠PQR + ∠QPR + ∠R = 180°

75° + ∠QPR + 90° = 180°

∠QPR = 15°

Since ∠QPR and ∠MQR share the same vertex Q, ∠QMP = 15°.

3. Determine the relationship between MP and MQ:

Since ∠QMP = 15° and ∠QMP + ∠MPQ + ∠Q = 180°, ∠MPQ = 150°.

Triangle MPQ is an isosceles triangle because ∠MPQ = ∠QMP. Therefore, MP = MQ.

4. Use trigonometry to find RQ:

In right triangle QMP, with ∠QMP = 15° and MP = 18:

sin(QMP) = MP / QM = 18 / QM

QM = 18 / sin(15°) = 18 * (1 / sin(15°)) (using the inverse sine function)

In right triangle MQR, with ∠MQR = 60° and QM calculated above:

sin(MQR) = QM / RQ = (18 * (1 / sin(15°))) / RQ

RQ = (18 * (1 / sin(15°))) / sin(60°) (using the cross-multiplication and sin ratio)

5. Calculate RQ:

sin(15°) ≈ 0.259 and sin(60°) ≈ 0.866

RQ = (18 * (1 / 0.259)) / 0.866 ≈ 82.45

Therefore, RQ ≈ 82.45 units.

User Dmitriy Kachko
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