Live GMAT classes with Target Test Prep start Nov 21 and Nov 22. First class free.

See classes
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.

Newsweek Readers’ Choice Awards 2026 winner: Target Test Prep, #1 Test Prep

Target Test Prep was voted #1 Best Test Prep in the 2026 Newsweek Readers’ Choice™ Awards.

★★★★★5.0563 reviews
GMATLiveTeachStarts Nov 22
Josh Braslow, Target Test Prep GMAT expert
LIVE ONLINE CLASSES

Get Ready for GMAT Test Day Faster with Live Online Classes

with Josh Braslow, 20+ years in test prep

Nov 22 · Josh Braslow
Sun · 9:30 AM to 12:30 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
EALiveTeachOnDemandStart anytime
EXECUTIVE ASSESSMENT

Target Test Prep EA OnDemand

Self-paced EA prep. Study on your schedule.

EXECUTIVE ASSESSMENT

with

165+ EA score guarantee
$05-day trial no automatic billing
Schedule
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
GMATOnDemandStart 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

tough geometry problem

Expert replies
by erukumk » Tue Oct 21, 2008 6:35 pm
how do i solve this??
You do not have the required permissions to view the files attached to this post.
Join the discussion
Source: — Problem Solving |

by aditi_bc » Tue Oct 21, 2008 10:37 pm
ANS is C. What is OA?
Join the discussion

by jsl » Wed Oct 22, 2008 2:07 am
I'm guessing C too. Definitely not A or B because the opposing angle can move. I'm not the best guy to explain geometry problems because I just "see" the solution in my head and I play with the shape (in my head).

If both of the lines are locked (because the 2 triangles are isoceles), then sliding the lines up and down does not alter the angle of x. Havign said that, I'm not precisely sure what x would be but I'm fairly sure that it's a constant solution and therefore C is the answer.
Join the discussion

by stop@800 » Wed Oct 22, 2008 10:44 pm
Ans is C

A and B alone are insufficient bcoz one side of angle is not fixed.

and the angle will be equal to 45 degree
Join the discussion

by amitabhprasad » Thu Oct 23, 2008 9:43 am
Is the angle 45 ?
I am getting the angle as 67.5 though I am getting answer as "C" as well

My mistake, I see what I missed.
Join the discussion

by rohangupta83 » Thu Oct 23, 2008 5:07 pm
imo C

X = 45 degrees

what's OA?
Join the discussion

by jsl » Fri Oct 24, 2008 12:40 am
rohangupta83 wrote:imo C

X = 45 degrees

what's OA?
How did you actually calculate that X=45? Can you step through the things you inferred?
Join the discussion

by rohangupta83 » Fri Oct 24, 2008 1:34 am
Sure jsl

here it is:

angle P = 90 degress
and

LP + LR + LT = 180...................................1

LRQS + LRSQ + LR = 180..........................2

LRQS = LRSQ (triangle RQS is an isosceles triangle).............3

equating 1 and 2

LP + LR + LT = LRQS + LRSQ + LR

or

90 + LT = LRQS + LRSQ

plugging equation 3 in the above equation

90 + LT = 2LRSQ
LT = 2LRSQ - 90.................eq 4

Now moving on to triangle TSU

LT + LTSU + LTUS = 180............5
LTSU = LTUS (triangle TSU is an isosceles triangle)
LT + 2 LTSU = 180

substituting for LT from equation 4 in equation 5

2LRSQ - 90 + 2LTSU = 180

2LRSQ + 2LTSU = 270

LRSQ + LTSU = 135.............................equation 6

now,

LRSQ + X + LTSU = 180 (angles on a straight line)

plugging equation 6 in the above equation

X + 135 = 180
or X = 45
Join the discussion