9514 1404 393
Answer:
11 cm
Step-by-step explanation:
The law of cosines can be helpful here. In order to find PQ, we must know the cosine of the angle R. Fortunately, SOH CAH TOA reminds us it is ...
Cos = Adjacent/Hypotenuse
cos(R) = 10/14 = 5/7
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The law of cosines gives us the relation ...
PQ^2 = PR^2 +QR^2 -2·PR·QR·cos(R)
PQ^2 = 15^2 +14^2 -2(15)(14)(5/7) = 121
PQ = √121 = 11
The length of PQ is 11 cm.
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<em>Alternate solution</em>
This can be solved using the Pythagorean theorem twice.
QS^2 = QR^2 -SR^2 = 14^2 -10^2 = 96
PQ^2 = PS^2 +QS^2 = 5^2 +96 = 121
PQ = √121 = 11
