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

Redeem
TTP OnDemand GMAT Video Course
Featured Course

Target Test Prep GMAT OnDemand

Scott Woodbury-Stewart’s private virtual classroom — 400 hours of master-class video lessons for the GMAT Focus Edition.

  • 715+ score guarantee — highest in the industry (99th percentile)
  • 52 chapters · 1,500+ lessons · 4,000+ practice questions
  • 400 hours of video · 1,500+ instructor-led HD smartboard lessons
  • 300,000+ students accepted to Harvard, Stanford, Wharton, Booth & Sloan & more
  • 24/7 live support + weekly Zoom office hours with GMAT instructors
  • TTP AI Assist — 24/7 AI-powered virtual tutor for instant help
  • 1,200+ flashcards + AI-powered study assistant & daily calendar
  • OnDemand, LiveTeach & GMAT Bootcamp formats available
  • Also: GRE, SAT Math & Executive Assessment courses
  • MBA Admissions Consulting now available
  • 🏆 2025 EdTech Breakthrough Award: Test Prep Solution Provider of the Year
  • 200,000+ students served
  • 5-day free trial — $0 to start, no auto-billing, cancel anytime
★★★★★ 5.0 (559 reviews)
130-pt guarantee
$0 to start then $127/mo
Start Free 5-Day Trial Read 559 Reviews →

Geometry

Expert replies
Post new topic Post Reply
Previous Topic Next Topic
User avatar
Master | Next Rank: 500 Posts
Posts: 489
Joined: Tue Jul 05, 2011 11:10 amFollowed by: 5 members
Thanked: 28 times
by gmatblood » Sun Nov 06, 2011 11:07 am
If f(x) = ax^2 + bx + c, and a does not equal 0, at what point does the graph of the function f(x) intersect the y-axis?

1)The graph of f(x) intersects the x-axis exactly twice, at (-6, 0) and (-2, 0)
2)a = 2

imo: C
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Source: — Data Sufficiency |
Legendary Member
Posts: 966
Joined: Sat Jan 02, 2010 8:06 amFollowed by: 21 members
Thanked: 230 times

by shankar.ashwin » Sun Nov 06, 2011 11:38 am
Given, y = ax^2 + bx + c, we need to find value of 'y' when 'x' = 0

When x=0, y = c.

Statement 1:

x= -6 -> 36a - 6b + c =0
x = -2 -> 4a - 2b + c = 0

Cannot solve for 'c' - 3 unknowns

Statement 2:

a = 2 (Not sufficient alone)

Together, 2 unknown 2 equations. C IMO
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
User avatar
Community Manager
Posts: 1060
Joined: Fri May 13, 2011 6:46 amFollowed by: 52 members
Location: Utrecht, The Netherlands
Thanked: 318 times

by neelgandham » Sun Nov 06, 2011 2:53 pm
If f(x) = ax^2 + bx + c, and a does not equal 0, at what point does the graph of the function f(x) intersect the y-axis?

The curve y = f(x) intersects the y axis at (0,c).We need to find the value of c in order to answer the question

1)The graph of f(x) intersects the x-axis exactly twice, at (-6, 0) and (-2, 0)

x= -6 => 36a - 6b + c =0
x= -2 => 4a - 2b + c = 0 Insufficient !

Common mistake - Committed by a friend of mine while practising

-6 and -2 are the roots of the equation.So, (x+6)*(x+2) = ax^2 + bx + c. i.e. c = 12. IT IS INCORRECT. If -6 is a root of the equation then the expression can be x+6 or 2x+12 or 3x+18 and so on... You will not be able to find the value of c, till you find the value of a

2)a = 2
Insufficient !

1) and 2) Sufficient !

IMO C
Anil Gandham
Welcome to BEATtheGMAT | Photography | Getting Started | BTG Community rules | MBA Watch
Check out GMAT Prep Now's online course at https://www.gmatprepnow.com/
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Post new topic Post Reply
• Page 1 of 1