- Finally we want to add a method
`getSolution`to solve the quadratic equation. Since the number of solutions can be 0, 1 or 2, it returns an array of appropriate length: QuadraticEquation.javaThe method computes the discriminant (i.e. the term under the square root) and arranges the terms according to the its sign.

- The standard class
`Math`contains a lot of mathematical functions as static methods, e.g.`sqrt`(square root),`sin`or`log`.

- The main routine creates a QuadraticEquation from the input parameters and
prints it, together with its solution:
TestQuadraticEquation.java
To do this, it needs to know the number of solutions. This can be extracted directly from the result array:

- An array has an integer field
`length`that contains the number of elements of the array.