TheQuadratic Formulaallows one to solve this sort of equation. The part of the Formula inside the square root is called "the discriminant", and allows you to determine the type of solution.

For a complete explanation, try some of the various lessonsavailable online. Once you are familiar with the discriminant and what information it provides, you will "see" why the solver went straight to the value of " ". :wink:

Have fun!