If \(y = x^2 - 6x + 9,\) what is the value of \(x?\) - The Beat The GMAT Forum

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Re: If \(y = x^2 - 6x + 9,\) what is the value of \(x?\)

by Scott@TargetTestPrep » Wed Jun 30, 2021 10:50 am

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Gmat_mission wrote: ↑
Thu Aug 27, 2020 8:10 am
If \(y = x^2 - 6x + 9,\) what is the value of \(x?\)

(1) \(y = 0\)
(2) \(x + y = 3\)

Answer: A

Source: Official Guide

Solution:

Question Stem Analysis:

We need to determine the value of x.

Statement One Alone:

Since y = 0, we can solve the equation:

x^2 - 6x + 9 = 0

(x - 3)^2 = 0

x - 3 = 0

x = 3

Statement one alone is sufficient.

Statement Two Alone:

Since x + y = 3, y = 3 - x and we can solve the equation:

x^2 - 6x + 9 = 3 - x

x^2 - 5x + 6 = 0

(x - 3)(x - 2) = 0

x = 3 or x = 2

Since x can be either 3 or 2, statement two alone is not sufficient.

Answer: A

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