Turn on thread page Beta
    • Thread Starter
    Offline

    0
    ReputationRep:
    |x|-3>1/3x
    My first solution was 9/2x which is correct
    And second was 9/4x which is wrong because it's meant to be minus and the graphs show that too.
    But I can't seem to figure out where I'm going wrong with the working..
    Using this to work out second solution gives me a positive
    -(x-3)=1/3x
    Offline

    10
    ReputationRep:
    (Original post by Liampayneisapain)
    |x|-3>1/3x
    My first solution was 9/2x which is correct
    And second was 9/4x which is wrong because it's meant to be minus and the graphs show that too.
    But I can't seem to figure out where I'm going wrong with the working..
    Using this to work out second solution gives me a positive
    -(x-3)=1/3x
    generally speaking if |x|>a this means -a<x<a
    so the first thing you need to do is to isolate your |x| by moving the -3 to the other side then applying the formula I said
    after that, go through every side of the inequality separately. so work through -a<x separate and x<a separate then combine the result. That should give you your -9/4<x for one of them!
    Offline

    11
    ReputationRep:
    (Original post by Liampayneisapain)
    |x|-3>1/3x
    My first solution was 9/2x which is correct
    And second was 9/4x which is wrong because it's meant to be minus and the graphs show that too.
    But I can't seem to figure out where I'm going wrong with the working..
    Using this to work out second solution gives me a positive
    -(x-3)=1/3x
    your error is in mistaking |x|-3 for |x-3|
 
 
 
Poll
Do you think parents should charge rent?
Useful resources

Make your revision easier

Maths

Maths Forum posting guidelines

Not sure where to post? Read the updated guidelines here

Equations

How to use LaTex

Writing equations the easy way

Student revising

Study habits of A* students

Top tips from students who have already aced their exams

Study Planner

Create your own Study Planner

Never miss a deadline again

Polling station sign

Thinking about a maths degree?

Chat with other maths applicants

Can you help? Study help unanswered threads

Groups associated with this forum:

View associated groups

The Student Room, Get Revising and Marked by Teachers are trading names of The Student Room Group Ltd.

Register Number: 04666380 (England and Wales), VAT No. 806 8067 22 Registered Office: International House, Queens Road, Brighton, BN1 3XE

Write a reply...
Reply
Hide
Reputation gems: You get these gems as you gain rep from other members for making good contributions and giving helpful advice.