Question

My current code that is not working correctly

#include<stdio.h>

#include<math.h>

int main() {

//variable declaration
int a,b,c,D,n;
double x1,x2;
double realPart, imagPart;

do {
// this set of code blocks prompts a message to the user and then read the integer entered and stores it as an integer
printf("Enter a value for a:\n");
scanf("%d",&a);
printf("Enter a value for b:\n");
scanf("%d",&b);
printf("Enter a value for c:\n");
scanf("%d",&c);
printf("You entered the Equation \n");
printf("%dx^2%+dx%+d=0\n",a,b,c);

D = b*b - 4*a*c;
  

if (D<0)
{
printf("Equation has two complex roots.\n");
realPart = -b/(double)(2*a);
imagPart = sqrt(-D)/(2*a);
printf("X= %.1lf%lfi or X= %.1lf%lfi\n", realPart, + imagPart, realPart, imagPart);
}
else { //real roots
x1 = (-b + sqrt(D))/(2*a);
x2 = (-b - sqrt(D))/(2*a);
if(x1==x2){
printf("Equation has two identical real roots.\n");
printf("x = %.2lf\n",x1);
}
else{
printf("X= %.1lf or X= %.2lf\n", x1, x2);
printf("Equation has two distinct real roots.\n");

}
  
}
printf("Another Equation? (Enter 0 to exit)...");
scanf("%d",&n);
}
while(n!=0);
}
WHAT THE CODE NEEDS TO DO IN C LANGUAGE ONLY

Write a program that determines whether a quadratic equation has one real root, two real roots, or imaginary roots. Then, if the roots are real, display the roots of the quadratic equation.

A quadratic equation is of the form ax^2+bx+c=0.

The discriminant of the equation is D=b^2-4ac. If D>0, then there are two distinct real roots. If D=0, then there are two identical real roots, and if D<0, then there are two imaginary roots.

The roots of the equation are found using the quadratic equation:

• Two Real Roots, D>0
  • x1,x2 = ( -b ± √(b^2-4ac) ) / (2a)
• One Real Root, D=0
  • x = (-b) / (2a)
• Two Imaginary Roots, D<0
  • x1,x2 = ( -b±i√( | b^2-4ac | ) ) / (2a)
    i=√(-1)

Procedure

• Include the usual (detailed) comment block including program name, author, date, inputs, outputs and description, followed by your preprocessor directives.
• After declaring your variables, explain the program to the user by printing a description to the monitor.
• Call a function that prompts the user for one of the values of the coefficients (a, b, or c) for the quadratic equation and returns the value entered, with error checking for a valid input (scanf returned a value). Note: this should be one function that gets called three times. The printf asking for the variable by name can be in main.
• Call a function to calculate the discriminant D.
• Use conditional statements to display the type of roots (one real, two real, or imaginary)
• Depending on the type of roots, use the appropriate form of the quadratic equation to calculate the roots of the equation and display them. For imaginary roots, you will need to calculate the real and imaginary parts separately and print them with the imaginary number i as part of the format. (Note: this means that you are doing real math. You don't need to figure out how to do imaginary math in C. Try calculating the last example below by hand to understand. When printing the imaginary roots, treat "i" simply as a letter/character to be displayed.)
• At the end of your program, offer the user the option to run again or exit.
• Do not forget to comment, use blank lines, and employ correct indentation.

Answer 1

Corrected code :

#include<stdio.h>

#include<math.h>

int main() {

//variable declaration
int a,b,c,D,n;
double x1,x2;
double realPart, imagPart;

do {
        // this set of code blocks prompts a message to the user and then read the integer entered and stores it as an integer
        printf("Enter a value for a:\n");
        scanf("%d",&a);
        printf("Enter a value for b:\n");
        scanf("%d",&b);
        printf("Enter a value for c:\n");
        scanf("%d",&c);
        printf("You entered the Equation \n");
        printf("%dx^2%+dx%+d=0\n",a,b,c);

        D = b*b - 4*a*c;
          

        if (D<0)
        {
                printf("Equation has two complex roots.\n");
                realPart = -b/(double)(2*a);
                imagPart = sqrt(-D)/(2*a);
                printf("X= %.1lf+%lfi or X= %.1lf-%lfi\n", realPart,  imagPart, realPart, imagPart);
        }
        else{ //real roots
                        x1 = (-b + sqrt(D))/(2*a);
                        x2 = (-b - sqrt(D))/(2*a);

                if (D==0){ //identical real roots
                
                        printf("Equation has two identical real roots.\n");
                        printf("x = %.2lf\n",x1);
                        }
                else{ // 2 distict real roots
                        printf("X= %.1lf or X= %.2lf\n", x1, x2);
                        printf("Equation has two distinct real roots.\n");
                }
          }
        printf("Another Equation? (Enter 0 to exit)...");
        scanf("%d",&n);
}
while(n!=0);
}

I have made the required corrections to your code and it is now working correctly.

Output :

Complex roots:

Identical real roots:

Identical distinct roots:

Screenshot of the code is attached so that you can understand the intendations.