What is the value of x if x^2 - 3x +2=0?

This question can be difficult to see where to start, but can be quite easily solved once you realise what you have to do Firstly, let ax2+ bx + c =0. If this is also true, a=1, b= -3, and c=2. 

Firstly, find the factors of a*c (= 2). You will find there are only two, 1 and 2, or -1 and -2. 

First take the pair 1 and 2, and see if there is a way to add these together to make b. You will see that there are no ways to add or subtract these numbers from each other to get -3.

Now try with the second pair, -1 and -2. You will see that -1+-2=-3, and so this is the pair we want. 

 Therefore, (x-1)(x-2)=0

If we now solve this new factorised equation, we can see that either (x-1)=0 or (x-2)=0. Now rearrange to get the answers.

(x-1)=0                OR              (x-2)=0

x=1                      OR               x=2

Answered by Charlotte S. Maths tutor

2375 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

Factorise x^2+3x+4 without the use of quadratic formula


Factorise fully: 3x - 9x^2


Simplify 125 ^ -2/3


How to work out a fraction of an amount?


We're here to help

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