A triangle PQR has angle PQR as 105 degrees. What is the area of

Question

A triangle PQR has angle PQR as 105 degrees. What is the area of triangle PQR?

(1) Length of PQ is 5 units.

(2) Angle PRQ is 30 degrees.

Miller116 · Answer

We can't find the area until we know the second side. A stmt not enough. Using B alone we can find the third angle but not side measurment

To use SIN theory we need angle and side. Using both the stmt we can find the area.

C

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LevanKhukhunashvili · Answer

There should be some other explanations, GMAT doesn't test SIN knowledge IMO

LevanKhukhunashvili · Answer

When I thought a bit, here is my approach:

We have to draw height PD from P angle to QR segment. No w we have got two right triangles PDR and PDQ
Lets check triangle PQD. Angle PQD is 45 degree and angle PDQ is 90 degree, we can find angle QPD=45. This triangle is isosceles right triangle with 45 degree phenomenon, As we know PQ=5 we can calculate every side.
Now let's check triangle PDR. As we know PRD angle is 30 degree and PDR angle 90 degree, we have got right triangle with 30 degree phenomenon and as we already know PD side we can calculate every side.

Area of the triangle PQR=PD*(QD+DR)/2

In My Opinion
Ans:  C

P.S Couldn't find how to attach files, to show the figure illustration. Sorry for my bad

cpanara · Answer

How can Angle PQD be 45?
PQD = 180-PQR => 180 - 105 => So PQD=75

cpanara · Answer

https://uploads.tapatalk-cdn.com/20180626/78c101a4f083ec6dbd6b517f768f644b.jpg

Attached solution

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A triangle PQR has angle PQR as 105 degrees. What is the area of

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