# How do you find the discriminant of x^2+4x-1=0 and use it to determine if the equation has one, two real or two imaginary roots?

Jun 27, 2017

The answer is given below.

#### Explanation:

In the equation

${x}^{2} + 4 x - 1 = 0$

a = 1, b = 4, c = -1

Discriminant = ${b}^{2} - 4 a c$

=> ${4}^{2} - 4 \times 1 \times \left(- 1\right)$

=> $16 - 4$

=> $12$

As the discriminant is greater than zero it means that the equation has two distinct real roots.