View Full Version : how to do dis

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

sorry gamer... don't really get how it goes

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

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.