Solve x^2 - x - 12

As it is a quadratic, I can use the quadratic equation, or (-b +/- sqrt(b2-4ac))/2aHere our a = 1, b = -1 and c = -12. Substitute into the quadratic equation, this becomes (1 +/- sqrt(1 + (4*12))/2 and then (1 +/- sqrt(49))/2Our answers will then be 1/2 + 7/2 and 1/2 - 7/2, which is equivalent to 4 and -3. Therefore our x = 4 and x = -3

FW
Answered by Freya W. Maths tutor

2988 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

A car costs £5,899.99, not including VAT. If the VAT rate is 20% how much does the car cost in total?


Prove that 0.5757... (recurring) = 19/33. Hence, write 0.3575757... (recurring) as a fraction in its lowest terms.


Find the coordinates of the point where lines 3x+5=y and 6y+x=11 intersect


The length of a rectangle is x+5 and the width is x+3. Write an equation for the area of the rectangle.


We're here to help

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

© MyTutorWeb Ltd 2013–2025

Terms & Conditions|Privacy Policy
Cookie Preferences