It is currently 13 Dec 2017, 09:13

# Decision(s) Day!:

CHAT Rooms | Ross R1 | Kellogg R1 | Darden R1 | Tepper R1

### GMAT Club Daily Prep

#### Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized
for You

we will pick new questions that match your level based on your Timer History

Track

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History

# Events & Promotions

###### Events & Promotions in June
Open Detailed Calendar

# For what value of x between -1 and 5

Author Message
TAGS:

### Hide Tags

Senior Manager
Joined: 27 May 2014
Posts: 320

Kudos [?]: 193 [0], given: 83

GMAT 1: 730 Q49 V41
For what value of x between -1 and 5 [#permalink]

### Show Tags

09 Oct 2017, 09:29
1
This post was
BOOKMARKED
00:00

Difficulty:

45% (medium)

Question Stats:

59% (01:17) correct 41% (00:42) wrong based on 113 sessions

### HideShow timer Statistics

For what value of x between -1 and 5 inclusive, is the value x^2 - 7x + 10 the smallest?

(A) -1
(B) 0
(C) 2
(D) 3
(E) 5
[Reveal] Spoiler: OA

Kudos [?]: 193 [0], given: 83

Director
Joined: 25 Feb 2013
Posts: 619

Kudos [?]: 306 [0], given: 39

Location: India
GPA: 3.82
For what value of x between -1 and 5 [#permalink]

### Show Tags

09 Oct 2017, 09:37
saswata4s wrote:
For what value of x between -1 and 5 inclusive, is the value x^2 - 7x + 10 the smallest?

(A) -1
(B) 0
(C) 2
(D) 3
(E) 5

$$x^2 - 7x + 10 = (x-5)(x-2)$$

For option A, B, C & E, this equation is either positive or 0. For Option D the equation is negative and hence the lowest

Kudos [?]: 306 [0], given: 39

Intern
Joined: 19 Sep 2016
Posts: 35

Kudos [?]: 2 [0], given: 3

Re: For what value of x between -1 and 5 [#permalink]

### Show Tags

09 Oct 2017, 09:46
Answer D. The equation gets simplified as (x-5)(x-2). So at 2&5, the equation is 0 so C & E options are out. Only for option D will the value be less than 0.

Sent from my SM-N920G using GMAT Club Forum mobile app

Kudos [?]: 2 [0], given: 3

Target Test Prep Representative
Affiliations: Target Test Prep
Joined: 04 Mar 2011
Posts: 1799

Kudos [?]: 981 [0], given: 5

Re: For what value of x between -1 and 5 [#permalink]

### Show Tags

12 Oct 2017, 17:14
saswata4s wrote:
For what value of x between -1 and 5 inclusive, is the value x^2 - 7x + 10 the smallest?

(A) -1
(B) 0
(C) 2
(D) 3
(E) 5

Let’s factor the given equation:

(x - 5)(x - 2)

We see that when x is 5 or 2, one of the factors will be 0; thus, the value of the expression is 0.

When x is -1 or 0, both factors will be negative, and thus the value of the expression is positive.

Finally, when x is 3, one factor is positive while the other is negative, and thus the value of the expression is negative.

We see, then, that the value of the expression is smallest when x = 3.

_________________

Jeffery Miller

GMAT Quant Self-Study Course
500+ lessons 3000+ practice problems 800+ HD solutions

Kudos [?]: 981 [0], given: 5

Manager
Joined: 07 Jul 2012
Posts: 219

Kudos [?]: 69 [0], given: 65

Location: India
Concentration: Finance
Re: For what value of x between -1 and 5 [#permalink]

### Show Tags

12 Oct 2017, 17:35
$$x^2$$-7x+2= (x-5)(x-2)

Put A in the above equation: (-1-5)(-1-2)= 18
Put B in the above equation: (0-5)(0-2)= 10
Put C in the above equation: (2-5)(2-2)= 0
Put D in the above equation: (3-5)(3-2)= -2 (Smallest Value)
Put E in the above equation: (5-5)(5-2)= 0

Kudos please if you like my explanation!

_________________

Kindly hit kudos if my post helps!

Kudos [?]: 69 [0], given: 65

Veritas Prep GMAT Instructor
Joined: 16 Oct 2010
Posts: 7792

Kudos [?]: 18112 [1], given: 236

Location: Pune, India
Re: For what value of x between -1 and 5 [#permalink]

### Show Tags

13 Oct 2017, 00:45
1
KUDOS
Expert's post
saswata4s wrote:
For what value of x between -1 and 5 inclusive, is the value x^2 - 7x + 10 the smallest?

(A) -1
(B) 0
(C) 2
(D) 3
(E) 5

Note that the given expression is a quadratic and its graph will be an upward facing parabola. So the minimum will be at x = -b/2a.
x = -(-7)/2*1 = 3.5
Of the given options, 3 is closest to 3.5 so that is where the expression will be minimum.
_________________

Karishma
Veritas Prep | GMAT Instructor
My Blog

Get started with Veritas Prep GMAT On Demand for \$199

Veritas Prep Reviews

Kudos [?]: 18112 [1], given: 236

Re: For what value of x between -1 and 5   [#permalink] 13 Oct 2017, 00:45
Display posts from previous: Sort by