# How do you find the value of the discriminant and determine the nature of the roots -2x^2-x-1=0?

##### 1 Answer
Apr 17, 2017

-7, no real roots

#### Explanation:

The discriminant is found using the equation ${b}^{2} - 4 a c$. Substitute the values from your equation into this one so:

a = -2 b = -1 c = -1

the discriminant will equal:
#(-1)^2 - 4 (-2) (-1) = -7

If the value of the discriminant is smaller than 0, then it has no real roots. If it's equal to 0, it has 1 real root, and if it's bigger than 0, it has 2 real roots.