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 →

Que: If \(4f\left(x\right)-3f\left(-x\right)=2x-7\), what is the value of \(f\left(3\right)\)?

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 amFollowed by: 37 members
Location: Las Vegas, USA
Thanked: 19 times
by Max@Math Revolution » Sat Jun 19, 2021 9:37 pm

Timer

00:00

Answers

A

B

C

D

E

Stats

Difficulty—

Que: If \(4f\left(x\right)-3f\left(-x\right)=2x-7\), what is the value of \(f\left(3\right)\)?

A) \(0\)

B) \(\frac{1}{7}\)

C) \(\frac{-43}{7}\)

D) \(\frac{36}{7}\)

E) \(\frac{43}{7}\)
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Source: — Problem Solving |
User avatar
Elite Legendary Member
Posts: 3991
Joined: Fri Jul 24, 2015 2:28 amFollowed by: 37 members
Location: Las Vegas, USA
Thanked: 19 times

Re: Que: If \(4f\left(x\right)-3f\left(-x\right)=2x-7\), what is the value of \(f\left(3\right)\)?

by Max@Math Revolution » Sun Jun 20, 2021 9:09 pm
Solution: 4f(x) - 3 f(-x) = 2x - 7 --------- equation (1)

Substituting x = 3 in equation (1)

=> 4f(3) - 3f(-3) = 2(3) - 7

=> 4f(3) - 3f(-3) = -1--------- equation (2)

Substituting x = -3 in equation (1)

=> 4f(-3) - 3f(3) = 2(-3) - 7

=> 4f(-3) - 3f(3) = -13--------- equation (3)

Multiplying equation (2) by ‘4’ we get,

=> 16f(3) - 12f(-3) = -4--------- equation (4)


Multiplying equation (3) by ‘3’ we get,

=> 12f(-3) - 9f(3) = -39--------- equation (5)

Adding Eqn(4) + Eqn(5)

=> 7f(3) = -43

=> f(3) = - \(\frac{43}{7}\)


C is the correct answer.

Answer C
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Post new topic Post Reply
• Page 1 of 1