Maths Olympiad Prep

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, 2021

Geometry Difficulty 2.5 Junior Find the answer Canada

In the diagram, PQRPQR is a straight line segment.

If x+y=76x + y = 76, what is the value of xx?

Pick one

Solution

Since PQRPQR forms a straight angle, then x+y+x+y+x=180x^\circ + y^\circ + x^\circ + y^\circ + x^\circ = 180^\circ which gives 3x+2y=1803x + 2y = 180.

Since x+y=76x+y=76 and 2x+2y+x=1802x+2y+x = 180, then 2(76)+x=1802(76) + x = 180 or x=180152=28x = 180 - 152 = 28.

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Source: CEMC, University of Waterloo, licensed CC-BY-NC-4.0. Statement reproduced verbatim; metadata (topic, difficulty) added by this project.