Implement the following two methods:
/** Return true if the sum of every two sides is
* greater than the third side. */
public static boolean isValid(
double side1, double side2, double side3)
/** Return the area of the triangle. */
public static double area(
double side1, double side2, double side3)
Write a test program that reads three sides for a triangle and uses the isValid method to test if the input is valid and uses the area method to obtain the area.
The program displays the area if the input is valid. Otherwise, it displays that the input is invalid. The formula for computing the area of a triangle is given in Programming Exercise 2.19.