第六章第三十五题（几何：五边形的面积）(Geometry: area of a pentagon)
6.35（几何：五边形的面积）五边形的面积可以使用下面的公式计算： 编写一个方法，使用下面的方法头来返回五边形的面积。 public static double area(double side) 编写一个主方法，提示用户输入五边形的边，然后显示它的面积。 下面是一个运行示例： Enter the side:5.5 The area of the pentagon is 52.044441 6.35(Geometry: area of a pentagon)The area of a pentagon can be computed using the following formula: Write a method that returns the area of a pentagon using the following header: public static double area(double side) Write a main method that prompts the user to enter the side of a pentagon and displays its area. Here is a sample run: Enter the side:5.5 The area of the pentagon is 52.044441参考代码：
package chapter06
;
import java
.util
.Scanner
;
public class Code_35 {
public static void main(String
[] args
) {
Scanner inputScanner
= new Scanner(System
.in
);
System
.out
.print("Enter the side: ");
double side
= inputScanner
.nextDouble();
double area
= area(side
);
System
.out
.printf("The area of the pentagon is %f", area
);
}
public static double area(double side
) {
double area
= (5 * Math
.pow(side
,2)) / (4 * Math
.tan(Math
.PI
/ 5));
return area
;
}
}
结果显示：
Enter the side
: 5.5
The area of the pentagon is
52.044441
Process finished with exit code
0
