Geometry kills me. I was doing so well until I hit this...

Question

Please note D is not the OA - rather it is my random guess after scratching my head for 5 mts.

walker · Answer

A

\frac{40}{360}=\frac{x}{18\pi}

x=2\pi

bsd_lover · Answer

How did you get the two 35 s at angle P. I know one of the 35's is because the two lines are parallel, how did u derive the other one ?

gdmat720 · Answer

the answer will be (A) 2 Pi

Explanation:

L(ARC PO)= 35/360 * 2*Pi*9
 =3.5 Pi.

Angle PRO and Angle QPR are same =35 (since Line OR is ll to PQ)

L(ARC PO) = L(ARC QR)=3.5 Pi

L(ARC OPQR)= 180/360 * 2*Pi*9 (Since Arc OPQR forms a semicircle hence theta = 180)
 =9 Pi.

hence 
L(OPQR) = L(Arc OP)+L(Arc PQ)+L(Arc QR)
L(Arc PQ) = 9 Pi - (3.5 Pi +3.5 Pi)
 = 2 Pi

Hence the Option A is correct.

sondenso · Answer

If still not get the point, let me know!

walker · Answer

the other angle is 35 because the triangle PR (center) is isosceles: P(center)=R(center)=radius.

bsd_lover · Answer

Yup got it .. thanks walker !!! +1.

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