MYTUTOR SUBJECT ANSWERS

149 views

Solve X^2 +13X+48=12

It is first important to get the equation to equal 0, so to do this you minus 12 from each side of the equals symbol, giving you

X^2 +13X+36=0

Now it is time to think about factorising!

The best trick for this is to find two numbers that multiply together to make the number without any X's (36 in this case) AND add together to make the number with an X after it (13 in this case).

So start by listing the factors of 36 in pairs:

6,6

3.12

1.36

4,9

2,18

Then turn each into an addition

6+6=12

3+12=15

1+36=37

4+9=13

2+18=20

As 4+9 equal 13 we know that the two numbers in our brackets are 4 and 9! If we had not been able to make our number with addition, you could try with negative numbers (eg if our middle number was -5 we could make this by doing 4+-9=-5). Practice and knowing your times tables well will help you spot these easier.

So we factorise the equation into brackets

(X+4)(X+9) 

each bracket has to equal 0 so

X+4=0       X=-4

X+9=0        X=-9

Kemba M. 13 Plus  Maths tutor, GCSE Maths tutor, 11 Plus Maths tutor,...

4 months ago

Answered by Kemba, a GCSE Maths tutor with MyTutor


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

453 SUBJECT SPECIALISTS

£18 /hr

Uthmaan I.

Degree: economics (Bachelors) - Durham University

Subjects offered: Maths, Economics

Maths
Economics

“I am currently an Economics student at Durham University. Through my passion of economics and maths, I hope to make sessions not only useful but also enjoyable. During the sessions, feel free to ask any questions in regard to what you...”

MyTutor guarantee

£20 /hr

Laura A.

Degree: Modern languages with business management (Bachelors) - Birmingham University

Subjects offered: Maths, Spanish+ 2 more

Maths
Spanish
French
Economics

“Hi my name is Laura! I'm 18 years old and I'm a first year student at the University of Birmingham studying French, Spanish and Business. I took the International baccelaureate in Sixth Form, and whilst it was a challenge, I really en...”

£18 /hr

Isaac H.

Degree: International Relations (Bachelors) - Exeter University

Subjects offered: Maths, History+ 1 more

Maths
History
Economics

“I have been tutoring professionally now for over a year. I am incredibly passionate about my students and have a genuine desire to see them succeed in their exams. I will put every minute of the lesson towards this goal. A survivor of...”

About the author

Kemba M.

Currently unavailable: for new students

Degree: Architecture (Bachelors) - Sheffield University

Subjects offered: Maths, History+ 2 more

Maths
History
Graphic Design
-Personal Statements-

“About me: Hello! I'm Kemba and I'm a first year undergraduate Architecture student at the University of Sheffield. I have a passion for three main subjects: History, Maths and Graphic Design, although I'm not studying any of these top...”

You may also like...

Posts by Kemba

Help, I have designers block!

How should I approach my GCSE maths paper?

How would I structure an essay?

Solve X^2 +13X+48=12

Other GCSE Maths questions

How to use trigonometry to find angles or lengths

Solve this quadractic equation: x^2 - 8x + 15 = 0

Solve the quadratic equation x^2 + 3x + 2 = 0, by factorisation.

How would I solve x^2 + 7x + 10 = 0

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