828 views

### How do you factorise a quadratic equation?

Take the example 2x2 + 7x + 3 = 0

1. To factorise we need to use the general equation 'ax + bx - c = 0'   where in our case a = 2 b =7 c=3.

2. First we need to mulitply the a and c values (2*3 = 6) where we have to find two numbers that will multiply to make 'ac' (6) and add to make 'b' (7)

3. It helps to list factors that make 6 and add to make 7. An example of what these factors could be is 6 and 1. Where  '6*1 = 6' and '6 + 1 = 7'

4. We then rewrite the equation to replace b with 6 and 1: 2x+ 6x + 1x +3 = 0 and find the common factor for both half of the equation.

5. The common factor for 2x2+ 6x is 2 and thus can be written as 2x(x + 3) where the second half of the equation x + 3 remains the same (x + 3). This can be written as (2x + 3) (x + 3) = 0

6. We can check if this is correct by expanding out the brackets.

2 years ago

Answered by Zartasht (Tashi), a Mentoring Maths tutor with MyTutor

## Still stuck? Get one-to-one help from a personally interviewed subject specialist

#### 0 SUBJECT SPECIALISTS

£22 /hr

Degree: Biological Science (Bachelors) - Birmingham University

Subjects offered:Maths, English+ 1 more

Maths
English
Biology

MyTutor guarantee

### You may also like...

#### Posts by Zartasht (Tashi)

How do you address a compare and contrast essay?

How do you factorise a quadratic equation?

What factors affect the speed at which an action potential travels?

What is the difference between mitosis and meiosis?

#### Other Mentoring Maths questions

What is a function and how does it differ from a polynomial?

How do you factorise a quadratic equation?

a ladder stands against a wall, then it slides down. Describe the motion of the centre of the ladder while sliding!

We use cookies to improve your site experience. By continuing to use this website, we'll assume that you're OK with this.