What can I say about the roots of a quadratic equation without actually calculating them?

If a quadratic equation is of the form ax2+bx+c, calculate D (Discriminant) whose value is b2-4ac. 

If the value of D is negative, the equation has imaginary roots.

If the value of D is positive, the equation has real and distinct roots.

If the value of D is zero, the equation has real and equal roots.

SS

Related Maths GCSE answers

All answers ▸

How do I find the x-intercept or the y-intercept?


Integrate y=3x+2 with respect to x between the bounds x=5 and x=0, and state the physical significance of this.


Lisa, Max and Punita share £240 in the ratio 3 : 4 : 8 How much more money than Lisa does Punita get?


(2x + 3y)^2 – (2x – 3y)^2 = 360 show that xy is a multiple of 5