Maths

>

GCSE

Algebra

Question

How do you solve an equation with x² in it?

2 years ago

·

1 Reply

·

1448 views

I

Isadore Quitzon


1 Answer

Liz R Profile Picture
Liz R Verified Sherpa Tutor ✓

Enthusiastic, Patient, Maths Teacher with 30 Years Experience.

5 reviews

Equations with x2 in them are called quadratics. There are three methods for solving quadratic equations.

The first is to factorise it if possible


E.g. x2+3x+2 = 0 becomes (x+2)(x+1)=0. 

Since one of these brackets must be worth zero to get the zero on the left-hand side then

either x+2=0 or x+1=0

so x=-2 or x=-1


You can also use the quadratic formula, which is useful if your equation will not factorise.

So if ax2+bx+c=0 then


x=

So if x2+3x+2 = 0 then here a=1, b= 3 and c=2. You then substitute these values into the formula using your calculator to find your answer.


Yet a further method is to complete the square.

I'm available for 1:1 private online tuition!

Click here to view my profile and arrange a free introduction.

Think you can help?

More Maths GCSE Questions
Sherpa Badge

Need a GCSE Maths tutor?

Get started with a free online introductions with an experienced and qualified online tutor on Sherpa.

Find a GCSE Maths Tutor