algebra - quadratic equation
This topic has expert replies
- Stuart@KaplanGMAT
- GMAT Instructor
- Posts: 3225
- Joined: Tue Jan 08, 2008 2:40 pm
- Location: Toronto
- Thanked: 1710 times
- Followed by:614 members
- GMAT Score:800
Let's start by expanding the expression:
(x^2 + 2xy + y^2)/(x^2 -2xy + y^2)
Now, let's rearrange things a bit:
(x^2 + y^2 + 2xy)/(x^2 + y^2 - 2xy)
Now, let's substitute the info from (1) into the expression:
(3xy + 2xy)/(3xy - 2xy) = 5xy/xy = 5... sufficient!
(x^2 + 2xy + y^2)/(x^2 -2xy + y^2)
Now, let's rearrange things a bit:
(x^2 + y^2 + 2xy)/(x^2 + y^2 - 2xy)
Now, let's substitute the info from (1) into the expression:
(3xy + 2xy)/(3xy - 2xy) = 5xy/xy = 5... sufficient!
Stuart Kovinsky | Kaplan GMAT Faculty | Toronto
Kaplan Exclusive: The Official Test Day Experience | Ready to Take a Free Practice Test? | Kaplan/Beat the GMAT Member Discount
BTG100 for $100 off a full course