simplify fully: (3x^2 - 8x -3)/(2x^2 -6x)

First of all, to simplify this fraction, we need to factorise the top and bottom equations. We shall start with the top equation. Now looking at the equation: 3x2 - 8x -3, we know that it's a quadratic with 3 different terms, so when we factorise this, it will look something like: ( _x +/- _ )( _x +/- _ ). We know that the two 'x' terms in the brackets need to multiply to make 3x2, so the coefficients of each of the x terms in brackets will be 3 and 1 because 3x1=3. So we now know that the brackets will look more like: (3x +/- _ )(x +/- _ ). We know that the two terms without an 'x' must multiply to make -3, so these coefficients must either be: ( -3 and 1 ) or ( 3 and -1 ). Now we need to deduce how to obtain the -8x from the coefficients that we have, and this will depend on which set of coefficients for the none-x term that we pick, and where we place them in the brackets. From a bit of trial and error we will find that the brackets should look like this: (3x+1)( x-3 ) because when we expand this the 'x' term will be made from (3x) x (-3) +(x)(1) which gives -9x +1x which is -8x.
Now when we factorise the 2x2 - 6x we simply get: 2x( x-3 ). So the fractions will look like: (3x+1)( x-3 )/2x( x-3 ). We can cancel out the ( x-3 ) terms on the top and the bottom of the fraction which will leave us with: (3x+1)/2x, which is the simplest version of this fraction.

Answered by Amanda H. Maths tutor

3168 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

The first four terms of an arithmetic sequence are : 11, 17, 23, 29. In terms of n, find an expression for the nth term of this sequence.


Find the highest common factor of 432 and 522


A) Raf, Jasmin and Carlos swim lengths of the pool for charity. Raf swims 30 more lengths than Jasmin. Jasmin swims four times as many lengths as Carlos. Altogether they swim 372 lengths. How many lengths each person swim?


(b) In 2013, the price for each unit of electricity was 13.5 cents. Over the next 3 years, this price increased exponentially at a rate of 8% per year. Calculate the price for each unit of electricity after 3 years


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 2013–2024

Terms & Conditions|Privacy Policy
Cookie Preferences