For what values of x is 2x^2 - 11x - 6 > 0 ?

The first step is to factorise the equation into two brackets. In this case we get (2x+1)(x-6)Now, for this to be greater than zero we need both brackets to be greater than zero, or both brackets to be less than zero. If one bracket was positive and the other negative, then the equation would be negative overall.So firstly, if they are both positive, 2x+1 > 0 tells us that x > -1/2. x - 6 > 0 tells us that x > 6. If we put these together then both inequalities have to be satisfied, so x has be be greater than 6. Now if they are both negative, 2x+1 < 0 tells us that x < -1/2. x-6 <0 tells us that x < 6. So overall x < -1/2 in order to satisfy both. So to conclude, we need x > 6 or x < -1/2 for the equation to be greater than zero.

RK
Answered by Rowan K. Maths tutor

3234 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

How can we calculate the sinus of 120°?


A four sided pyramid, with a vertical height of 10cm and the base 4cmx4cm is placed on the top of a cylinder with radius 1.5cm and a height of 15cm. What is the exposed surface area?


When will I use this in my everyday life?


Rearrange to make p the subject. C + 5 p = a ( C – p )


We're here to help

contact us iconContact usWhatsapp logoMessage us on Whatsapptelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

© MyTutorWeb Ltd 2013–2025

Terms & Conditions|Privacy Policy
Cookie Preferences