Solve by factorisation: 2(x^2) - 5x - 12 = 0

First step is to multiply coefficient of first term (2) with the constant (-12) to enable us to split the middle term.2*(-12) = -24, therefore we need to find two numbers that multiply to -24, and add to give the coefficient of the second term (-5). These two numbers are -8 and 3 as these numbers add to give -5 and multiply to give -24. Therefore we can split the middle term: 2x2 - 8x + 3x - 12 = 0By factorising:2x(x - 4) + 3(x - 4) = 0, (x - 4)(2x + 3) = 0.If (x - 4) = 0, x = 4.If (2x + 3) = 0, x = - 1.5.Therefore, solutions for x for this quadratic equation are x = 4, -1.5.

EC
Answered by Edward C. Maths tutor

5298 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

Solve these pair of simultaneous questions: 3x+2y=17 4x-y=30


Work out: 20% of 12000


The point P(-3,9) belongs to a line intercepting the origin. Find the equation of the line.


(a) show that 3/10 + 2/15 = 13/30 (b) show that 2 5/8 ÷ 1 1/6 = 2 1/4


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