By completing the square, find the solutions of x which satisfy the equation x^2+14x-1=0

Using the general complete the square formula, where x2+bx+c=0 becomes (a+b/2)2+b2+c=0, we get (x+7)2-72-1=0 This can be rearranged to show that (x+7)2=50 by taking the square root of both sides we find that x+7=+ or - √50 Hence the final solutions are x=-7 +√50 and x=-7-√50

Answered by Immie F. Maths tutor

2061 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

How can i use completing the square to factorise and solve equations


These are the selling prices of 5 houses in 2007: £145 000, £170 000, £215 000, £90 000, £180 000. Work out the mean selling price.


Sketch a graph of the equation of y=3x+2


if b is two thirds of c. 5a = 4c Work out the ratio a : b : c


We're here to help

contact us iconContact usWhatsapp logoMessage us on Whatsapptelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo
Cookie Preferences