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

3737 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

Solve for x: 2x^2 = 5x + 12


x^2 = 4(x – 3)^2


The two points (4,9) and (2,3) are on line A. A second line, line B is perpendicular to line A and goes through the point (2,3). What is the equation of line B?


I decrease a number by 26%, the answer is 9 x10^-7, what was the original number?


We're here to help

contact us iconContact ustelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

MyTutor is part of the IXL family of brands:

© 2026 by IXL Learning