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

Redeem

If x^2 + 10y^2 - 6xy – 2y + 1 = 0, what is the value of x?

This topic has expert replies
Post new topic Post Reply
Previous Topic Next Topic
User avatar
Elite Legendary Member
Posts: 3991
Joined: Fri Jul 24, 2015 2:28 am
Location: Las Vegas, USA
Thanked: 19 times
Followed by:37 members

If x^2 + 10y^2 - 6xy – 2y + 1 = 0, what is the value of x?

by Max@Math Revolution » Thu Jul 18, 2019 11:52 pm

Timer

00:00

Your Answer

A

B

C

D

E

Global Stats

[GMAT math practice question]

If x^2 + 10y^2 - 6xy - 2y + 1 = 0, what is the value of x?

A. 0
B. 1
C. 2
D. 3
E. 4
Top
Source: — Problem Solving |
User avatar
Elite Legendary Member
Posts: 3991
Joined: Fri Jul 24, 2015 2:28 am
Location: Las Vegas, USA
Thanked: 19 times
Followed by:37 members

by Max@Math Revolution » Sun Jul 21, 2019 5:31 pm
=>

x^2 + 10y^2 - 6xy - 2y + 1 = 0
=> x^2-6xy+10y^2-2y+1=0
=> x^2-6xy+9y^2+y^2-2y+1=0
=>(x-3y)^2+(y-1)^2=0
=> x=3y and y=1

Thus, x = 3.
Therefore, the answer is D.
Answer: D
Top
Post new topic Post Reply
• Page 1 of 1