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gamer
11-15-2006, 04:52 PM
A Sector was given,(Imagine figure like, a triangle PQR having its base subtended by an arc(QR),A line(PS) bisects the triangle to form another radius.Find the length of base of triangle.Radius given as 5,distance between base of traiangle and arc = 1cm?????

gamer
11-15-2006, 07:49 PM
pl help in dis

moe
11-15-2006, 10:42 PM
sorry gamer... don't really get how it goes

een
11-16-2006, 05:08 AM
Hello, gamer!
Does the answer equal 6 cm ?
een

gamer
11-16-2006, 05:14 AM
how did u get that ...answer im not aware picked it frm a forum for GRE ...its the latest GRE question

een
11-16-2006, 05:23 AM
Am I right that P is a center of the circle with radius 5 cm and PR=PQ= 5cm?

If I am right, you should consider triangle QPR, drop a perpendicular PS on QR, (so S belongs to QR) , a line PS bisects the triangle, hence QS=SR, then QR=2*SR and
PR^2=SR^2+PS^2 (Pythagorean theorem)

After that consider the point M(for a example), M belongs to arc QR,
and if it is a circle, hence PM=PR=QP=5cm=PS+SM, so PS=4cm

At last SR^2=PR^2-PS^2 , hence SR=3 and QR=6 cm.

All the best!
een

zaga3
11-16-2006, 05:24 AM
The answer is 6. Since the triengle has equal sides( redius of the arc) the bisector is perpendicular to the base of the triangle.The triangle will have 5 as hypotenuse and (5-1=4) as opposite side and 3 as the base.
So 3*2= 6 which is the length of the base.