BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course

Redeem
TTP OnDemand GMAT Video Course
Featured Course

Target Test Prep GMAT OnDemand

Scott Woodbury-Stewart’s private virtual classroom — 400 hours of master-class video lessons for the GMAT Focus Edition.

  • 715+ score guarantee — highest in the industry (99th percentile)
  • 52 chapters · 1,500+ lessons · 4,000+ practice questions
  • 400 hours of video · 1,500+ instructor-led HD smartboard lessons
  • 300,000+ students accepted to Harvard, Stanford, Wharton, Booth & Sloan & more
  • 24/7 live support + weekly Zoom office hours with GMAT instructors
  • TTP AI Assist — 24/7 AI-powered virtual tutor for instant help
  • 1,200+ flashcards + AI-powered study assistant & daily calendar
  • OnDemand, LiveTeach & GMAT Bootcamp formats available
  • Also: GRE, SAT Math & Executive Assessment courses
  • MBA Admissions Consulting now available
  • 🏆 2025 EdTech Breakthrough Award: Test Prep Solution Provider of the Year
  • 200,000+ students served
  • 5-day free trial — $0 to start, no auto-billing, cancel anytime
★★★★★ 5.0 (559 reviews)
130-pt guarantee
$0 to start then $127/mo
Start Free 5-Day Trial Read 559 Reviews →

gmat maths geometry

Expert replies
Post new topic Post Reply
Previous Topic Next Topic
Senior | Next Rank: 100 Posts
Posts: 96
Joined: Fri Apr 23, 2010 1:14 amFollowed by: 1 member
Thanked: 1 times
by quantskillsgmat » Sat Dec 17, 2011 10:33 pm
If a and b are sides of a traingle and area of this triangle is given as 1/4(a^+b^2).
what are angles of this traingle.
a)60-60-60
b)30-60-90
c)90-45-45
d)80-70-30
e_100-50-30
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Source: — Problem Solving |
Legendary Member
Posts: 1084
Joined: Fri Apr 15, 2011 2:33 pmFollowed by: 21 members
Thanked: 158 times

by pemdas » Sat Dec 17, 2011 11:42 pm
i assume the power of 2 such as a^2 below
quantskillsgmat wrote:If a and b are sides of a traingle and area of this triangle is given as 1/4(a^2+b^2).
what are angles of this traingle.
a)60-60-60
b)30-60-90
c)90-45-45
d)80-70-30
e_100-50-30
this is theoretical question, and we need to try out diff. triangles. I tried the right triangle at first and got it right

c
Image
Success doesn't come overnight!
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Legendary Member
Posts: 966
Joined: Sat Jan 02, 2010 8:06 amFollowed by: 21 members
Thanked: 230 times

by shankar.ashwin » Sat Dec 17, 2011 11:50 pm
Not sure if the question is correct..

Area = 1/4 * (a^2 + b^2)

60-60-60 - let the side be '1' unit -> area = Sqrt(3)/4

1/4 * (a^2 + b^2) = 1/4 * (2) = 1/2 -> both are not equal eliminate


30-60-90

sides are in ratio 1 : sqrt(3) : 2 -> area = bh/2 = Sqrt(3)/2

1/4 * (a^2 + b^2) = 1/4 * (1 +3) = 1 -> eliminate

90-45-45

let b=h=1, area = 1/2

1/4 * (a^2 + b^2) = 1/4 * (1 + 1) = 1/2

Should be C IMO

Now sure how to check options D and E. Whats the OA?
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Legendary Member
Posts: 1084
Joined: Fri Apr 15, 2011 2:33 pmFollowed by: 21 members
Thanked: 158 times

by pemdas » Sat Dec 17, 2011 11:59 pm
by setting arbitrarily a=h for one side you restrict the possibilities for that side. I'd rather test by setting base freely and letting the height (h) be one-half of base (h=b/2). Then you can test opposite angle<->side relationship further and see that options d and e are not correct. For description, plz the see the pic in previous post.
shankar.ashwin wrote: Now sure how to check options D and E. Whats the OA?
Success doesn't come overnight!
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Post new topic Post Reply
• Page 1 of 1