In the xy-plane above, is angle QPR a right angle?

[BTGmoderatorDC]

In the xy-plane above, is angle QPR a right angle?

(1) Points P and Q have the same x-coordinate.
(2) Points P and R have the same y-coordinate.

OA C


Source: Official Guide

[Jay@ManhattanReview]

In the xy-plane above, is angle QPR a right angle?

(1) Points P and Q have the same x-coordinate.
(2) Points P and R have the same y-coordinate.

OA C

Source: Official Guide

We know that the two axes in xy-plane make 90º. If we are able to prove that PQ is parallel to Y-axis and PR is parallel to X-axis, we can conclude that segments PQ and PR intersect at 90º; thus, /_QPR is 90º.

From Statement 1, we know that PQ is parallel to Y-axis and from Statement 2, we know that PR is parallel to X-axis; thus, /_QPR is 90º. Sufficient.

The correct answer: C

Hope this helps!

-Jay
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