MYTUTOR SUBJECT ANSWERS

295 views

How do I solve a quadratic equation?

The best way to solve a quadratic function is to put brackets into the equation.

Start with an example

Find x when y=0 for the function 

y=x*2 + 5x + 6

As y=0 make the whole equation= 0:

x*2 + 5x + 6=0

Try and put this into brackets:

(x+a)(x+b)=0 (as all the values are positive, we know that there are going to be no negative signs in the brackets).

Now we just need to find values for a and b that multiply out to give us the equation we need.

Try a=6 and b=1:

This gives us the 6 at the end but when multiplied out gives us 7x- which is too much.

Now try a=2 and b=3 and multply out:

We get 0=x*2+ 2x + 3x + 6= x*2 + 5x + 6 ... which is what we want!

So we get (x+2)(x+3)=0

For it to equal 0 either:

x+2=0 so x=-2 or

x+3=0 so x=-3

so x=-2, -3

Rosiered B. GCSE Biology tutor, A Level Biology tutor, GCSE Maths tut...

10 months ago

Answered by Rosiered, a GCSE Maths tutor with MyTutor


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

334 SUBJECT SPECIALISTS

£18 /hr

Balraj D.

Degree: PPE (Philsophy, Politics & Economics) (Bachelors) - Warwick University

Subjects offered: Maths, Philosophy+ 4 more

Maths
Philosophy
French
Economics
Chemistry
.TSA. Oxford.

“Hi! I'm Bal! Currently studying Philosophy, Politics and Economics in my first year at university and really enjoying myself. I got a score of 41 in my IB Diploma, 11 points above the world average. I also gained 10A*s in my GCSEs. In ...”

£18 /hr

Erin B.

Degree: Biomedical Sciences (Bachelors) - Durham University

Subjects offered: Maths, Spanish+ 1 more

Maths
Spanish
Biology

“About me: I am currently in my first year studying Biomedical Sciences at Durham University. Prior to coming to the U.K., I completed the International Baccalaureate Diploma Program at an international school in Tokyo, Japan. I come ...”

MyTutor guarantee

£18 /hr

Matthew H.

Degree: Physics (Masters) - Liverpool University

Subjects offered: Maths, Physics+ 3 more

Maths
Physics
History
Chemistry
-Personal Statements-

“About Me  I am studying physics at the University of Liverpool and am now in my second year having passed with a first in all my modules last year. I really love all things science and have a real drive to pass on what I know to other...”

About the author

Rosiered B.

Currently unavailable: for new students

Degree: Biomedical sciences (Bachelors) - Durham University

Subjects offered: Maths, Psychology+ 1 more

Maths
Psychology
Biology

“About meMy name is Rosiered Brownson-smith and I study Biomedical Sciences at Durham University. I have a passion for science and maths! I pride myself on being friendly, enthusiastic and approachable- so don't hesitate to get in tou...”

MyTutor guarantee

You may also like...

Other GCSE Maths questions

How do I find the length of a side of a triangle using the cosine rule?

How should I go about factorising x^2+5x+6?

Find the inverse of y = 2x+1/ x-1

Eleri invests £3700 for 3 years at 2% per annum compound interest. Calculate the value of her investment at the end of the 3 years. Give your answer correct to the nearest penny.

View GCSE Maths tutors

Cookies:

We use cookies to improve our service. By continuing to use this website, we'll assume that you're OK with this. Dismiss

mtw:mercury1:status:ok