Solve the quadratic equation 3x^2 + x – 5 = 0 give answers to 3 decimal places

To solve this quadratic equation we should first see if it is possible to factorise it into two seperate brakets. In this case there are no numbers which multiply to give -5 and add to give 3. Thus we should resort to using the quadratic formula which is used when equations cannot be solved by inspection. The quadratic formula is x=(-b+-(b2-4ac)1/2)/2a. Values for a,b and c can be lifted from the question. ax2+b-c=0 so in this question a=3 b=1 and c=-5. Inputing these into the equation will give two results. The answers are x=1.135 or x=-1.468 both of these answers make the original equation true.

David R. GCSE Maths tutor

2 years ago

Answered by David, a GCSE Maths tutor with MyTutor

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


£24 /hr

Scott R.

Degree: PGCE Secondary Mathematics (Other) - Leeds University

Subjects offered:Maths, Further Mathematics

Further Mathematics

“I am currently completing 2 PGCEs in Leeds. I have always had a passion for maths and my objective is to help as many as possible reach their full potential.”

£22 /hr

Sophie H.

Degree: Mathematics (Masters) - Bristol University

Subjects offered:Maths, Further Mathematics

Further Mathematics

“I’ll help anyone finding maths hard. I still struggle now, it's not meant to be easy! Be at my tutorial or (c^2-a^2) <- a maths joke, I apologise.”

£22 /hr

Hinsum W.

Degree: Medicine (Bachelors) - Edinburgh University

Subjects offered:Maths, Chemistry+ 3 more

-Personal Statements-
-Medical School Preparation-

“I'm a 3rd year Edinburgh medic currently intercalating in Anaesthesia. I am a seasoned tutor and can improve your exam technique and subject knowledge!”

About the author

David R.

Currently unavailable: for regular students

Degree: Economics and Management (Bachelors) - Bristol University

Subjects offered:Maths


“I am currently reading economics at Bristol University. I have always thoroughly enjoyed mathematics and hope to be able to instill that same enthusiasm in you too. I am a patient person. I have coached hockey for children aged 5 to 1...”

MyTutor guarantee

You may also like...

Other GCSE Maths questions

Pythagoras' Theorem

The line l is a tangent to the circle x^2 + y^2 = 40 at the point A. A is the point (2, 6). The line l crosses the x-axis at the point P. Work out the area of triangle OAP.

Sarah’s collection contains dresses, skirts and blouses. If the ratio of dresses to skirts is 7 to 4 and the ratio of skirts to blouses is 7 to 2, what is the ratio of dresses to blouses?

If f(x)=7-4x, given that f(c)=9, find c

View GCSE Maths tutors

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