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Triangle P Q R is shown. Angle R P Q is 99 degrees and angle P Q R is 31 degrees. The length of Q R is 11. Determine the measures of all unknown angles and side lengths of ΔPQR. Round side lengths to the nearest hundredth. m∠R = ° PR ≈ PQ ≈

User COLD TOLD
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2 Answers

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Answer:R=50 PR=5.74 PQ=8.53

Explanation:

On edge:)

User Bhavesh Jethani
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7 votes

Answer:

m∠R = 50 degrees

PR ≈ 5.74 units

PQ ≈ 8.53 units

Explanation:

Let's first find the measure of the third angle, which should be easier to find. Remember that the total degree measure of a triangle is 180, so all three angles should add up to 180. Here, we already have <RPQ = 99 and <PQR = 31. So, <PRQ = 180 - 99 - 31 = 50 degrees.

We need to use the law of sines to figure out the lengths of the other two sides. The law of sines states that for a triangle with angles A, B, and C and side lengths a, b, and c, respectively:
(a)/(sinA) =(b)/(sinB) =(c)/(sinC)

Here, we can say that a = PR, b = QR, c = PQ, A = <PQR, B = <RPQ, and C = <PRQ. Then, we have:


(a)/(sinA) =(b)/(sinB) =(c)/(sinC)


(PR)/(sin(PQR)) =(QR)/(sin(RPQ)) =(PQ)/(sin(PRQ))

We know that QR = 11, <RPQ = 99, <PQR = 31, and <PRQ = 50, so we can try to find PR:


(PR)/(sin(PQR)) =(QR)/(sin(RPQ))


(PR)/(sin(31)) =(11)/(sin(99))


PR =(11)/(sin(99))*sin(31)5.74 units

Now, let's find PQ:


(QR)/(sin(RPQ)) =(PQ)/(sin(PRQ))


(11)/(sin(99)) =(PQ)/(sin(50))


(11)/(sin(99))*sin(50) =PQ8.53 units

Hope this helps!

User Iacopo Boccalari
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