Solve x^2 + 4x + 4 = 0

To solve this equation we have two different methods:

1) We can solve this method 'by hand' and is done by knowing how to factorise the quadratic and is done by looking at the equation given to us to find hints that will help solve it.

(x " first symbol " a) (x " second symbol" b) = 0

WIthout going too in depth:

the second symbol "+" tells us that the two symbols in our answer are the same

the first symbol "+" combined with the knowledge of second symbol "+" tells us that the two symbols in our answer are both "+"

next we know "a" times "b" = 4 and "a" + "b" = 4 so we find numbers that match this description e.g. 2 and 2 and so we have found our answer

x^2 + 4x + 4 = 0 = (x+2)(x+2) 

and so x = -2 

2) Using the quadratic formula:

 (-b +- sqrt(b^2 - 4ac))/2

This method is simpler and requires you to only plug in the numbers in the correct place of the formula, the a, b and c from the formula come from the general equation: ax^2 + bx + c which all quadratic formulas can be related to. 

e.g.) ax^2 + bx + c and so a = 1, b = 4 c = 4 in our example

and our result is -2

King Him  C. GCSE Maths tutor, A Level Maths tutor, GCSE Chemistry tu...

4 months ago

Answered by King Him , a GCSE Maths tutor with MyTutor

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


Jonathan B. A Level Chemistry tutor, GCSE Chemistry tutor, A Level Ma...
View profile
£18 /hr

Jonathan B.

Degree: Chemistry (Masters) - Oxford, Lincoln College University

Subjects offered: Maths, Physics+ 1 more


“Hi, my name is Jonny and I have just finished my first year studying Chemistry at Oxford University, taking modules inChemistry, Physics and Maths. I have experience tutoring secondary school maths and science students and I have a pa...”

PremiumSarah W. A Level Maths tutor, GCSE Maths tutor, A Level Chemistry tut...
View profile
£22 /hr

Sarah W.

Degree: Robotics (Masters) - Bristol University

Subjects offered: Maths, Physics+ 3 more


“About Me: I am currently a Masters student in Robotics at the University of Bristol. My choice of degree was based on my love for hands on science. I will try to pass on this love to you during my tutorials! I have alot of experience...”

Peter W. A Level Maths tutor, A Level Further Mathematics  tutor, A L...
View profile
£18 /hr

Peter W.

Degree: Aerospace Engineering (Masters) - Queen's, Belfast University

Subjects offered: Maths, Physics+ 1 more

Further Mathematics

“Second year Aerospace Engineering student at Queen's University Belfast. Happy to offer help in Maths, Further Maths and Physics at GCSE and A-Level, which I have great experience in both learning and tutoring.”

About the author

King Him  C. GCSE Maths tutor, A Level Maths tutor, GCSE Chemistry tu...
View profile
£18 /hr

King Him C.

Degree: Computer Science (Masters) - Durham University

Subjects offered: Maths, Chemistry


“Hello there! I am a Computer Science undergraduate studying at Durham University. I am very enthusiastic about the understanding of scientific concepts and also the core ideas and building blocks of subjects. I have been tutoring duri...”

MyTutor guarantee

You may also like...

Other GCSE Maths questions

How to determine the number of unique real roots of a quadratic equation.

A cylindrical beaker has a height of 16 cm and a diameter at its bottom of 10 cm. What is its volume? Give your answer to 2 decimal places.

There are 200 students in Year 10. 110 are boys. There are 250 students in Year 11. 140 are boys. Which year has the greater proportion of boys?

What if my equation doesn't factorise?

View GCSE Maths tutors


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