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"Exception in thread "main" java.util.MissingFormatArgumentException: Format specifier '%.4f'"

I'm looking to print the surface area and volume in 4 decimal places using %.4f. I have no clue what the error in the title means. Here is the source code:
import java.util.Scanner;
public class VolumeAndSurfaceArea {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
// Radius is abbrebriated to "r"
double r = sc.nextDouble();
double SA = 4.0 * 3.14 * r * r;
double V = 4/3 * 3.14 * r * r * r;
double helper_SA = SA;
System.out.printf("The Surface Area is: %.4f" + SA);
System.out.printf("The Volume is: %.4f" + V);
}
}
Any help would be appreciated. Thanks!

Rather than concatenating the double values to the end of your String messages, add them to the argument list like so:
System.out.printf("The Surface Area is: %.4f", SA);
System.out.printf("The Volume is: %.4f", V);

Java :calculate the circle diameter and

this is a Class about calculating diameter,circumference and area of circle that user enter radius value and it gives him diameter,cirucumf... ,
this is the class code:
package circle;
import java.util.Scanner;
public class Circle {
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
int radius=0;
int diameter;
int circumference ;
int area;
int Pi;
Pi=(int) 3.14;
area = (int) (radius*radius*Pi);
circumference =(int)(radius*2*Pi);
diameter = (int)(radius*2);
System.out.print("Enter radius value:");
radius=input.nextInt();
System.out.printf("area is %d%n" , area);
System.out.printf("diameter is %d%n", diameter);
System.out.printf("circumference is %d%n", environment);
}
}
this is what output gives me :
Enter radius value: (for exmaple) 4
area is 0 // (real value is 50.24)
diameter is 0 // (8)
circumference is 0 //(25.12)
what is the code problem?
or how can i fix it?

You read the radius AFTER computing area/environment(?)/diameter. Furthermore, your values are int variables, which also means that your value for pi is just 3. I suggest you correct the order of the statements, and start using double instead of int.

"environment" will be replaced by "circumference". As your excepted output is decimal value. So use float/double instead of int. In your program you are calculating diameter,circumference and area after initialising the value of radius(radius=0) but before getting the value of radius(radius=4). I have modified your code. It seem help you.
package circle;
import java.util.Scanner;
public class Circle {
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
int radius=0;
float diameter;
double circumference ;
double area;
double Pi;
Pi= 3.14;
System.out.print("Enter radius value:");
radius=input.nextInt();
area = (radius*radius*Pi);
circumference =(radius*2*Pi);
diameter = (radius*2);
System.out.printf("area is " + area);
System.out.printf("\ndiameter is "+ diameter);
System.out.printf("\ncircumference is "+ circumference);
}
}

you are calculating the values area/environment(?)/diameter before getting and initializing the radius input.And at that time the default value for radius is set which is 0. Hence it is giving the results of all the parameters as 0.So you will have to re order your code as below:
System.out.print("Enter radius value:");
radius=input.nextInt();
area = (int) (radius*radius*Pi);
environment=(int)(radius*2*Pi);
diameter = (int)(radius*2);
System.out.printf("area is %d%n" , area);
System.out.printf("diameter is %d%n", diameter);
System.out.printf("environment is %d%n", environment);

Area of a Pentagon

I was trying to write a code to take the radius of a pentagon and turn it into a side, then output the area. Somewhere along the way my use of the math class is incorrect. (New to this site but tried to format everything so you could understand my program)
Class: CS 1301/16
// Term: Fall
// Name: Gabriel Tomasetto
// Intsructor: Ms. Tulin
// Assignment 1
import java.util.*;
public class Pentagon {
public static void main(String[] args) {
Scanner scan = new Scanner(System.in);
double radius, side, area;
System.out.println("Please enter the length of the Pentagon from the center to the vertex: ");
radius = scan.nextDouble();
side = (2 * radius) * (Math.sin(Math.PI/5)); //I'm assuming I'm not correctly using the Math class to represent the equation? Thoughts.
area = (5 * Math.pow(radius, 2)) / (4 * Math.tan(Math.PI /5));
System.out.println("The area of the Pentagon is:\t" + area);
}
}

Shouldn't it be side = (2 * radius) * (Math.sin(Math.PI/2/5));?
What's the error you're getting? Just the wrong answer?
Just a simple tpyo I think, try this.
area = (5 * Math.pow(side, 2)) / (4 * Math.tan(Math.PI /5));
...assuming this is the right formula using side length and not radius
http://www.mathopenref.com/polygonregulararea.html

How to get the circumference, area and radius of a circle in java?

I'm trying to print out the radius, circumference and area of a circle, and it is not working. I'm a complete beginner at java and coding so thank you for the help.
public class program54c {
public static void main (String args[]) {
double pi = 3.14159;
double radius = 15.337;
double circumference = (2*pi*radius);
double area = (pi*(radius*2));
System.out.println("The radius of the circle" = radius);
System.out.println("The circumference of the circle" = circumference);
System.out.println("The area of the circle" = area);
}
}

Your code seems correct except for one thing (assuming you know your mathematical calculations).
System.out.println("The radius of the circle" = radius);
You are not using the correct string concatenation for your output.
Replace = with + and try. For example,
System.out.println("The radius of the circle " + radius);

In your print statements, you need to use the + operator instead of = to append the variables value to your string. For example
"The area of the circle " = area
should be
"The area of the circle " + area
this will concatenate (append) the value of area to the string "The area of the circle "
Full example below:
public class program54c
{
public static void main (String args[])
{
double pi = 3.14159;
double radius = 15.337;
double circumference = (2*pi*radius);
double area = (pi*(radius*2));
System.out.println("The radius of the circle " + radius);
System.out.println("The circumference of the circle + circumference);
System.out.println("The area of the circle " + area);
}
}

I spot two errors in your code:
The string concatenation, as precised in the others answers, must be done with + and not =.
radius * 2 is not radius² ! You should use Math.pow(radius, 2) or radius*radius.
On a side note, you can use Math.PI instead of your own pi.

Law of Cosines used to find third side - why do I get the wrong result?

I keep getting an output of 45.8 when inputting 24 as side a, 32 as side b and 115 as angle C
the correct angle is 47.4
can someone please tell me what I'm doing wrong?
The calculation is:
double sideC = Math.sqrt((Math.pow(sideA, 2) + Math.pow(sideB, 2))- 2*(sideA*sideB)*(Math.cos(angleC)));
Source:
import java.util.Scanner;
public class TriangleCalc
{
/**
* #param args
*/
public static void main(String[] args)
{
System.out.println(" Triangle Calculator ");
Scanner inputab = new Scanner(System.in);
System.out.println("Input lenghts of sides 'a' and 'b':");
double sideA = inputab.nextDouble();
double sideB = inputab.nextDouble();
System.out.println("Input the size of Angle C in degrees:");
double angleC = inputab.nextDouble();
inputab.close();
double sideC = Math.sqrt(((Math.pow(sideA, 2) +
Math.pow(sideB, 2))- (2*(sideA*sideB)*(Math.cos(angleC)))));
System.out.println("\t /\\\n\t / \\\n\t / \\\n\t/ \\");
System.out.printf(" %3.1f",sideA);
System.out.print("/ \\");
System.out.printf("%3.1f",sideB);
System.out.println("\n / \\\n / \\\n"
+" /______________\\");
System.out.print(sideC);

As the Javadoc for Math.cos states
a - an angle, in radians.
You need to convert degrees to radians if you want to use degrees.
You can use Math.toRadians
Replace
Math.cos(angleC)
with
Math.cos(Math.toRadians(angleC))