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

Redeem

Value x^2+y^2?

This topic has expert replies
Post new topic Post Reply
Previous Topic Next Topic
Newbie | Next Rank: 10 Posts
Posts: 7
Joined: Mon Jan 31, 2011 1:54 pm
Thanked: 1 times

Value x^2+y^2?

by RWO » Fri May 20, 2011 6:22 pm
What is the value of x^2 + y^2 ?
(1) x^2 + y^2 = 2xy + 1
(2) x^2 + y^2 = 4 - 2xy



Source:GmatHacks.com
Top
Source: — Data Sufficiency |
Legendary Member
Posts: 1084
Joined: Fri Apr 15, 2011 2:33 pm
Thanked: 158 times
Followed by:21 members

by pemdas » Fri May 20, 2011 7:42 pm
st(1) can be further simplified as (x-y)^2=1 <> x-y=|1|, Not Sufficient;
st(2) ditto here (x+y)^2=4 <> x+y=|2|, Not Sufficient;

combined st(1&2): since we have mods there is more than one value for x when st(1) is added to st(2).
IOM e
RWO wrote:What is the value of x^2 + y^2 ?
(1) x^2 + y^2 = 2xy + 1
(2) x^2 + y^2 = 4 - 2xy



Source:GmatHacks.com
Success doesn't come overnight!
Top
User avatar
Legendary Member
Posts: 1309
Joined: Mon Apr 04, 2011 5:34 am
Location: India
Thanked: 310 times
Followed by:123 members
GMAT Score:750

by cans » Mon Jun 06, 2011 9:38 pm
What is the value of x^2 + y^2 ?
(1) x^2 + y^2 = 2xy + 1
(2) x^2 + y^2 = 4 - 2xy
a)insufficient. (1 equation, 2 variables)
b)insufficient. (1 equation, 2 variables)
a & b together) xy=3/4 thus x^2 + y^2 = 1+3/2 = 5/2
Sufficient.
IMO C
If my post helped you- let me know by pushing the thanks button ;)

Contact me about long distance tutoring!
[email protected]

Cans!!
Top
Master | Next Rank: 500 Posts
Posts: 217
Joined: Tue May 31, 2011 9:42 pm
Thanked: 8 times
Followed by:2 members

by garima99 » Tue Jun 07, 2011 10:26 pm
Add the two equations
2(x^2 + y^2)=5
IMO C
Top
Senior | Next Rank: 100 Posts
Posts: 32
Joined: Mon Mar 21, 2011 8:39 am
Location: Chennai
Thanked: 1 times
Followed by:3 members

by kruthika » Wed Jun 08, 2011 12:20 am
The two statements together will give a solution.
IMO c
Top
Post new topic Post Reply
• Page 1 of 1