Chapter 8, Problem 9PC

Geometry Calculator

Design a Geometry class with the following methods:

• A static method that accepts the radius of a circle and returns the area of the circle. Use the following formula:

   Area = πr²

Use Math.PI for π and the radius of the circle for r.

• A static method that accepts the length and width of a rectangle and returns the area of the rectangle. Use the following formula:

   Area = Length × Width

• A static method that accepts the length of a triangle’s base and the triangle’s height. The method should return the area of the triangle. Use the following formula:

   Area = Base × Height × 0.5

The methods should display an error message if negative values are used for the circle’s radius, the rectangle’s length or width, or the triangle’s base or height.

Next, write a program to test the class, which displays the following menu and responds to the user’s selection:

Geometry Calculator

1. 1. Calculate the Area of a Circle
2. 2. Calculate the Area of a Rectangle
3. 3. Calculate the Area of a Triangle
4. 4. Quit

Enter your choice (1-4):

Display an error message if the user enters a number outside the range of 1 through 4 when selecting an item from the menu.