SOLUTION: PQR is an isosceles triangle such that QP=QR=13cm and the altitude PS=12cm. Find the length of PR.

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Question 91774: PQR is an isosceles triangle such that QP=QR=13cm and the altitude PS=12cm. Find the length of PR.
Answer by mathispowerful(115) About Me  (Show Source):
You can put this solution on YOUR website!
This problem can be solved by using Pythagorean-theorem twice.
First find QS: QS%5E2+=+QP%5E2+-+PS%5E2
QS%5E2+=+13%5E2+-+12%5E2+
QS%5E2 = 25
QS = 5
Then RS = QR - QS = 13 - 5 = 8
PR = sqrt%28PS%5E2+%2B+RS%5E2%29
PR = sqrt%28144+%2B+64%29
PR = sqrt%28208%29
PR = 4%2Asqrt%2813%29
or PR = 14.42