GMAT Question of the Day - Daily to your Mailbox; hard ones only

 It is currently 23 Oct 2019, 07:01

### 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

# If p and q are the roots of the quadratic equation ax^2+bx+c = 0,

 new topic post reply Question banks Downloads My Bookmarks Reviews Important topics
Author Message
Director
Joined: 18 Feb 2019
Posts: 582
Location: India
GMAT 1: 460 Q42 V13
GPA: 3.6
If p and q are the roots of the quadratic equation ax^2+bx+c = 0,  [#permalink]

### Show Tags

29 Mar 2019, 00:19
2
00:00

Difficulty:

55% (hard)

Question Stats:

60% (01:22) correct 40% (01:41) wrong based on 52 sessions

### HideShow timer Statistics

If p and q are the roots of the quadratic equation ax^2+bx+c = 0, where a*b*c ≠ 0, is the product of p and q greater than 0?

I. |p + q| = |p| + |q|

II. ac > 0
NUS School Moderator
Joined: 18 Jul 2018
Posts: 1020
Location: India
Concentration: Finance, Marketing
WE: Engineering (Energy and Utilities)
If p and q are the roots of the quadratic equation ax^2+bx+c = 0,  [#permalink]

### Show Tags

31 Mar 2019, 11:04
1
3
$$ax^2+bx+c = 0.$$
Sum of the roots = p+q = -b/a
Product of roots = pq = c/a
Question, whether $$c/a > 0$$?

From S1:

|p+q| = |p| +|q|
Only possible when both p and q are either positive or negative.
In either of the cases c/a will be greater than 0.
Hence Sufficient.

From S2:

ac > 0.
Then either a and c are both positive or negative.
Hence Sufficient.

D is the answer.
_________________
Press +1 Kudos If my post helps!
Intern
Joined: 26 Aug 2018
Posts: 3
Re: If p and q are the roots of the quadratic equation ax^2+bx+c = 0,  [#permalink]

### Show Tags

01 Apr 2019, 10:03
Please elaborate the explanation

Posted from my mobile device
NUS School Moderator
Joined: 18 Jul 2018
Posts: 1020
Location: India
Concentration: Finance, Marketing
WE: Engineering (Energy and Utilities)
Re: If p and q are the roots of the quadratic equation ax^2+bx+c = 0,  [#permalink]

### Show Tags

01 Apr 2019, 10:20
Tulsi123 wrote:
Please elaborate the explanation

Posted from my mobile device

Hey Tulsi123, Which part of my explanation is not clear?
_________________
Press +1 Kudos If my post helps!
Re: If p and q are the roots of the quadratic equation ax^2+bx+c = 0,   [#permalink] 01 Apr 2019, 10:20
Display posts from previous: Sort by

# If p and q are the roots of the quadratic equation ax^2+bx+c = 0,

 new topic post reply Question banks Downloads My Bookmarks Reviews Important topics

 Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne