Just one sec...
Hey! Sign in to get help with your study questionsNew here? Join for free to post

Inequalities

Announcements Posted on
    • Thread Starter
    Offline

    ReputationRep:
    I have the inequality:
    -2<\frac{2x}{5}\leq3
    I have to find all the possible integer values of x in the inequality above.
    First I multiplied both sides by 5 to get:
    -10<2x\leq15
    I then divided the first sub-inequality (SI 1) by 2:
    (SI 1) -10<2x
    (SI 1) -5<x
    I then divided the second sub-inequality (SI 2) by 2:
    (SI 2) 2x\leq15
    (SI 2) x\leq7.5
    Through combining SI 1 and SI 2 I form the following:
    -5<x\leq7.5

    Here comes the easiest part of all, but somehow the hardest at the moment for me. I now have to find all the possible integer values of x. I easily understand that -5 will NOT be included as a possible integer because of the sign next to it. However the 7.5 part with the sign confuses me. :confused:

    Is 8 included or not? WHY?
    Or do I just have the possible integers to be:
    -4,-3,-2,-1,0,1,2,3,4,5,6 and 7 ?

    Whether 8 gets included or not, please explain to me why.
    Thanks a lot.
    Offline

    ReputationRep:
    7.5 would be in there if it were an integer

    but the most your x can be is 7.5, so how could it b 8?
    Offline

    ReputationRep:
    the inequality sign is less than or equal to so everything up to and including 7.5 is a value of x but nothing about that so 8 wouldnt be
    • Thread Starter
    Offline

    ReputationRep:
    THANKS a LOT !

Reply

Submit reply

Register

Thanks for posting! You just need to create an account in order to submit the post
  1. this can't be left blank
    that username has been taken, please choose another Forgotten your password?
  2. this can't be left blank
    this email is already registered. Forgotten your password?
  3. this can't be left blank

    6 characters or longer with both numbers and letters is safer

  4. this can't be left empty
    your full birthday is required
  1. Oops, you need to agree to our Ts&Cs to register
  2. Slide to join now Processing…

Updated: April 10, 2012
TSR Support Team

We have a brilliant team of more than 60 Support Team members looking after discussions on The Student Room, helping to make it a fun, safe and useful place to hang out.

Poll
Should the UK have more bank holidays?
Useful resources

Make your revision easier

Maths

Maths Forum posting guidelines

Not sure where to post? Read here first

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
Study resources

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

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