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Aug 14Harvard Business School's round 1 MBA application deadline is nearly 4 weeks away
12:00 PM PDT
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Watch Personal MBA Coach's quick tips video to learn how to position yourself for success:
Aug 14How to Write an Effective MBA Statement of Purpose (SoP) | MBA Application Essays
03:00 PM PDT
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Preparing the Statement of Purpose is at the core of the applications process. This detailed conceptual video shall help you in preparing an impactful SoP that will lift up the overall quality of your MBA Application.
Aug 15All GRE Prep Club Tests are free and open on August 15th in Celebration of India's Independence Day!
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This Monday, GRE Prep Club Tests will be Absolutely Free! 12 AM - 11:59 PM PDT
Aug 15Explore truly Personalized GRE Prep (Free trial)
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Targeting a 330+? Try out the most methodical and personalized GRE prep course that uses adaptive learning technology to help you prepare effectively.
Aug 15Learn About TTP's Elite, One-On-One Online Tutoring
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Target Test Prep Expert Tutors know how to handle every aspect of the GRE. Ready to get started? Schedule a free consulting call today!- Aug 16
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Whether you’re starting from scratch with your GRE or you’ve been preparing for the GRE for a while, Target Test Prep has a personalized study plan that can help you reach your goal. 
Aug 18How to Write a Compelling MBA Goals
04:30 PM PDT
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Writing a compelling essay about your goals requires that you reflect on your experiences to date and how you might leverage resources at an MBA program to address areas for development.
Aug 18PATH TO GRADUATE SCHOOL
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Interested in graduate school but not sure how to get there? In this session, we will discuss why getting a graduate degree is valuable, the steps you need to take to apply to graduate school, and how the GRE helps prospective students gain an advantage.
Retired Moderator
Joined: 07 Jun 2014
Posts: 4805
GRE 1: Q167 V156
WE:Business Development (Energy and Utilities)
If x + y = –3 and x2 + y2 = 12, what is the value of 2xy?
[#permalink]
23 Jun 2018, 11:49
23 Jun 2018, 11:49
Expert Reply
00:00
Question Stats:
84% (00:44) correct
15% (01:55) wrong based on 32 sessions
Hide Show timer Statistics
If \(x + y = -3\) and \(x^2 + y^2 = 12\), what is the value of \(2xy\)?
_________________
Show: :: OA
-3
_________________
Sandy
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Re: If x + y = –3 and x2 + y2 = 12, what is the value of 2xy?
[#permalink]
25 Jun 2018, 07:03
25 Jun 2018, 07:03
Ans. -3
Retired Moderator
Joined: 07 Jun 2014
Posts: 4805
GRE 1: Q167 V156
WE:Business Development (Energy and Utilities)
Re: If x + y = –3 and x2 + y2 = 12, what is the value of 2xy?
[#permalink]
28 Jul 2018, 16:07
28 Jul 2018, 16:07
Expert Reply
Explanation
One of the “special products” you need to memorize for the GRE is \(x^2 + 2xy + y^2 = (x + y)^2\).
Write this pattern on your paper, plug in the given values, and simplify, solving for 2xy:
\(x^2 + 2xy + y^2 = (x + y)^2\)
\((x^2 + y^2) + 2xy = (x + y)^2\)
\((12) + 2xy = (–3)^2\)
\(12 + 2xy = 9\)
\(2xy = –3\)
_________________
One of the “special products” you need to memorize for the GRE is \(x^2 + 2xy + y^2 = (x + y)^2\).
Write this pattern on your paper, plug in the given values, and simplify, solving for 2xy:
\(x^2 + 2xy + y^2 = (x + y)^2\)
\((x^2 + y^2) + 2xy = (x + y)^2\)
\((12) + 2xy = (–3)^2\)
\(12 + 2xy = 9\)
\(2xy = –3\)
_________________
Sandy
If you found this post useful, please let me know by pressing the Kudos Button
Try our free Online GRE Test
If you found this post useful, please let me know by pressing the Kudos Button
Try our free Online GRE Test
gmatclubot
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