Triangle

This topic has expert replies
Junior | Next Rank: 30 Posts
Posts: 18
Joined: Tue Mar 06, 2007 8:57 am

Triangle

by gmatme » Wed Apr 11, 2007 11:47 am
I know QS = 5 and PRS and PRQ are similar. How do i calculate PR?
PRS is 45-45-90 triangle?
Attachments
20.doc
(34 KiB) Downloaded 110 times

User avatar
Community Manager
Posts: 789
Joined: Sun Jan 28, 2007 3:51 pm
Location: Silicon valley, California
Thanked: 30 times
Followed by:1 members

by jayhawk2001 » Wed Apr 11, 2007 9:12 pm
We have to use properties of similar triangles here.

Triangle QPS and Triangle PRS are similar triangles with right angle
at P and R respectively.

PR/QP = PS/QS

PR = QP * PS/QS
= 3 * 4 / 5
= 12/5

Legendary Member
Posts: 559
Joined: Tue Mar 27, 2007 1:29 am
Thanked: 5 times
Followed by:2 members

by Cybermusings » Thu Apr 12, 2007 3:31 am
This one is pretty simple. Since the 2 sides are 3 (PQ) and 4 (PS) respectively, the hypotenuese QS becomes 5
Thus area of triangle PQS = 1/2 * 3 * 4 (taking PS as the base and PQ as the height)
1/2 * 5 * PR (taking QS as the base and PR as the height)
1/2*5*R = 1/2*3*4
Therefore R = 12/5