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 7 seats left
Chris Peckover
NEXT LIVE COHORT

Oct 13 to Jan 7, 2027

with Chris Peckover

Schedule
Tue, Thu · 8:00 to 10:00 PM ET
Included
40 live hours + 6 months of GMAT OnDemand
  • Live instruction and real-time questions
  • Class recordings and assigned practice
View class & enroll
Limited cohort · enrollment openTarget Test Prep
EALiveTeach 5 seats left
Logan Thompson
EXECUTIVE ASSESSMENT

Sep 6 to Dec 6, 2026

with Logan Thompson

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
Limited cohort · enrollment openTarget 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

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

Square inscribed in a circle (Powerprep Practice Test)

Expert replies
by jcan-gmatter » Fri Oct 05, 2007 11:38 am
Hello,

How do I approach the following problem? I was using Brahmagupta's formula but I'm getting 16Pi as the answer, which is incorrect. That is

Square Root (S-a) (S-b) (S-c) (S-d)

where S = a + b + c + d /2

See attached image.
Attachments
geometry.jpg
Join the discussion
Source: — Problem Solving |

by mschling52 » Fri Oct 05, 2007 11:54 am
I would use the formula (a^2)+(b^2) = (c^2) (pythagorean theorem), where a and b are the legs of a right triangle and c is the hypotense.

If you draw a right triangle by connecting 2 corners of the square, you will note that the hypotenuse of the right triangle you create is also the diameter of the circle. Each side of the square is length 4 (since the area is 16). Therefore, the length of the hypotenuse of the right triangle (and the diameter of the circle) can be solved by

(4^2)+(4^2) = c^2
32 = c^2
sqrt(32) = c
4sqrt(2) = c (you could also get this quicker by knowing the ratios for a 45-45-90 triangle)

Since we know the diameter of the circle is 4sqrt(2), we also know the radius is 2sqrt(2). Then we can calculate the area of the circle as

pi*(2sqrt(2))^2 = 8*pi
Join the discussion

Didn't think of the triangle angle

by jcan-gmatter » Fri Oct 05, 2007 12:13 pm
Hello,

Thank you for the response. Looked at the figure for quite a bit but didn't figure that I could use the triangle route. Will definitely keep this in mind.

/Thanks.
Join the discussion