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

Redeem

Target Test Prep · GMAT

Choose how you want to prepare

Learn live with an expert or move at your own pace. Every option includes the complete TTP study system.

★★★★★5.0559 reviews
GMATLiveTeach Starts Oct 17
Chris Peckover, Target Test Prep GMAT expert
LIVE ONLINE CLASSES

Get Ready for GMAT Test Day Faster with Live Online Classes

with Chris Peckover, 100th-Percentile GMAT Scorer

Oct 17 · Chris Peckover
Sat · 11:00 AM to 2:00 PM ET
Oct 20 · Chris Peckover
Tue, Thu · 8:00 to 10:00 PM ET
Oct 25 · Josh Braslow
Sun · 1:00 to 4:00 PM ET
Included
40 hours of live online classes + 6 months of TTP OnDemand
  • Attend the first class for free
  • Every class is recorded, so you never fall behind
View classes & enroll
Limited seats availableTarget Test Prep
EALiveTeachOnDemand 5 seats left Start anytime
EXECUTIVE ASSESSMENT

Target Test Prep EA OnDemand

Self-paced EA prep. Study on your schedule.

Logan Thompson
EXECUTIVE ASSESSMENT

Sep 6 to Dec 6, 2026

with Logan Thompson

165+ EA score guarantee
$05-day trial no automatic billing
Schedule
Sun · 9:30 AM to 12:30 PM ET
Included
40 hours of live online classes plus six months of access to the complete TTP EA OnDemand course.
  • 165+ EA Score Guarantee
  • 4,100+ Quant, Verbal, and Integrated Reasoning practice questions
  • 400+ hours of in-depth video lessons
  • 3,000+ step-by-step video solutions
View EA class & enroll Start free 5-day trial
Limited cohort · enrollment openTrial includes full course accessTarget Test Prep
GMATOnDemand Start anytime
SELF-PACED MASTERCLASS

Target Test Prep GMAT OnDemand

Complete access from day one. Study on your schedule.

715+ score guarantee
$0to start then $127/mo
  • Personalized study plan and analytics
  • Thousands of lessons and practice questions
Start free 5-day trial
Read 559 reviewsTarget Test Prep

Compare the format, schedule, and included access before enrolling. Prices and seat counts shown reflect the supplied offer details.

Geometry mystery! OG 11 - Quant Review(green) DS#109

Expert replies
Post new topic Post Reply
Previous Topic Next Topic
Newbie | Next Rank: 10 Posts
Posts: 9
Joined: Fri Jun 05, 2009 10:48 am
by alex.gmat » Tue Jul 14, 2009 4:51 pm
Hello all!
I am seeking your expert advice on a problem that confuses me. Thank you in advance!

We are given a rectangular region with length l , width w, and diagonal d

What is the area of the rectangular region?

1. l + w = 6
2. d^2 = 20


The OA confuses me greatly! In particular, why the Pythagorean theorem cannot be used to solve the problem, since it is true that for every rectangle D = sqrt (x^2 + y^2) and that a diagonal in a rectangle divides it into two identical 30-60-90 triangles??

Thank you again for your input!

Alex
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Source: — Data Sufficiency |

GMAT/MBA Expert

User avatar
GMAT Instructor
Posts: 2623
Joined: Mon Jun 02, 2008 3:17 amFollowed by: 355 members
Location: Montreal
Thanked: 1090 times
GMAT Score:780

Re: Geometry mystery! OG 11 - Quant Review(green) DS#109

by Ian Stewart » Tue Jul 14, 2009 5:38 pm
alex.gmat wrote:
The OA confuses me greatly! In particular, why the Pythagorean theorem cannot be used to solve the problem, since it is true that for every rectangle D = sqrt (x^2 + y^2) and that a diagonal in a rectangle divides it into two identical 30-60-90 triangles??
The diagonal of a rectangle does not normally divide the rectangle into two 30-60-90 triangles. In fact, that will only happen if the ratio of the length to the width is equal to root(3) to 1. If you think of a square (which is a rectangle), for example, the diagonal divides it into two 45-45-90 triangles.
For online GMAT math tutoring, or to buy my higher-level Quant books and problem sets, contact me at ianstewartgmat at gmail.com

ianstewartgmat.com
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Newbie | Next Rank: 10 Posts
Posts: 9
Joined: Fri Jun 05, 2009 10:48 am

by alex.gmat » Tue Jul 14, 2009 9:00 pm
Thank you for the reply!
My bad on the 30-60-90 statement - your clarification totally makes sense; however, does d=sqrt(x^2 + y^2) still hold true for any rectangle? If it does, why can't we use this with statement (2) to solve the problem?

Thank you again!
I just wanted to say how helpful this forum has been in the process of my preparation for the GMAT. To everyone involved - you rock!

A.
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Senior | Next Rank: 100 Posts
Posts: 52
Joined: Tue Jan 27, 2009 9:44 am
Thanked: 4 times

My answer for the above question...

by struggling_guy2001 » Tue Jul 14, 2009 9:51 pm
I strongly feel that both the statements are required and enough to solve the problem.

Use the Phythagoras theorem

i.e.

(Length) ^2 + ( Breadth ) ^2 = ( Diagonal )^2.

By solving the equation. we get L= 2 or 4 and B = 4 or 2.

Hence the are would be 8 sq.units in both the cases.

Hence I would go for the option Both the statements are enough and required to solve the problem.
Anyone from Hyderabad or Telugu speaking community.

Searching for a serious study partner from Hyderabad or the one who work for same Company.
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Post new topic Post Reply
• Page 1 of 1