# How to use the discriminant to find out what type of solutions the equation has for #2x^2 + x - 1 = 0#?

##### 1 Answer

May 21, 2015

The discriminant

Since this is positive, the equation

Additionally, since it is a perfect square (and the cofficients of the quadratic are rational), those roots are rational.

In fact, they are given by the formula:

That is, the solutions are