Solve the following inequality: x^2 + x -12<0

Firstly we have to factorize the quadratic. We do this by finding two numbers that multiply to -12 and add to 1.Looking at the factors of 12 we can see that x2+x-12= (x-3)(x+4)because -3 x 4 = 12 and 4-3=1. Now we can draw a graph to help us solve this inequality. We know the graph cut the x-axis at 3 and -4 because that is when the brackets equal 0. Finally we can shade the section of the graph where y<0 and this will help us write our inequality answer of:-4<x<3

JS

Related Maths GCSE answers

All answers ▸

Simplify: 2x + 6y + 2y - x


How would you solve the simultaneous equations 2x + y = 7 and 3x - y = 8


Solve simultaneous equations: 3x + y = 12 and 5x + 5y = 30


P is directly proportional to Q. When Q = 6, P = 15. Work out the value of P when Q = 3.5