Solve the equation "x^2 + 3x - 4 = 0".

Recognise that quadratic can be factorised:

(x+4)(x-1)=0

This gives the solutions x=-4 and x=1 by inspection.

ZK

Related Maths GCSE answers

All answers ▸

a)By completing the square, prove the quadratic formula starting from ax^2+bx+c=0, b) hence, or otherwise solve 3x^2 + 7x -2= 9, to 3s.f.


1ii) sketch y=x^2-4x-21


A quarter circle has a radius of 8, calculate the area giving your answer in terms of pi


Solve the simultaneous equations for x and y: 2x+4y=-12 and y=-x-2