PQR is an isosceles triangle with PQ = QR. If mQPR = 40°, what is mPQR?

30°

40°

60°

80°

100°

Question

PQR is an isosceles triangle with PQ = QR. If mQPR = 40°, what is mPQR?

    30°

    40°

    60°

    80°

    100°

anonymous · Answer

For an isosoceles triangle, if two sides are the same length, then the two nonincluded angles are the same measure. A generic picture of that would be:

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As in the two sides marked x are the same length and the angles marked $\alpha$ are the same measure. Since that is true, see if you can piece together the measure of the angle you need :)

anonymous · Answer

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