Quadratic equation (in our case ) has the following solutons:
For these solutions to exist, the discriminant should not be a negative number.
First, we need to compute the discriminant : .
Discriminant d=340 is greater than zero. That means that there are two solutions: .
Quadratic expression can be factored:
Again, the answer is: 0.219544457292887, 18.2195444572929.
Here's your graph:
