x(squared) - 7x - 18 > 0(adsbygoogle = window.adsbygoogle || []).push({});

Right I know what to do, you factorise the quadratic etc.

So you get (x + 2)(x - 9) > 0

I though -2<x<9 but apparently I'm wrong? I always get confused when it comes to using GREATER THAN/ LESS THAN signs and having to find a set of values which satisfy the equation. When are the x values greater than or greater and equal etc. ?

I'm sorry if I may not be explaining my problem very well, a simple question which commonly occurs in our AS-Level Maths papers but just don't know how to write the set of x values which satisfy the equation, when is it greater than or less than etc.

Thanks.

1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

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# Simple maths problem (Greater than/Less than) help

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