2x^2+21x=-40

2x2+21x+40=0factors of 40=1&40, 2&20, 4&10, 5&85 & 8 are correct factors as 5 + 2*8 = 21(2x+5)(x+8)=0So, x = -8 & -2.5

NM

Related Maths GCSE answers

All answers ▸

Solve the simultaneous equations 3x + y = 11 and 2x + y = 8.


Expand the following expression: -5x(x-7)(x+3)


A is the point with coordinates (1, 3) B is the point with coordinates (–2, –1) The line L has equation 3y = 4 – 2x Is line L parallel to AB?


Solve the quadratic equation x^2 + 7x + 6 = 0