Solve Quadratic Equation- Program Codes

Quadratic equation is most popular equation to solve many scientific problems. In mathematics a quadratic equation is   defined as a polynomial equation with degree 2 using single variable.  We can Solve Quadratic Equation using the standard formula.

It is written as 

ax^2 + bx + c= 0

Such that a, b and c ∈ R and a ≠ 0.  The values of a, b and c are called coefficients of the terms with degree of 2, 1 and 0 respectively.  The quadratic equation always defined with single variable. The values of a, b and c that satisfy the quadratic equation are called the roots of the quadratic equation.  The quadratic equation will always be solvable by exactly two roots. The roots are real or imaginary.

The formula to calculate two roots of the quadratic equation is 

(y,z)= (-b (+/-) squareroot(b^2-4*a*c))/2* a

 (+/-) allows you to create two roots with this formula, one by addition and one by subtraction.

 Type of roots of Quadratic Equation

Depending on the value of D= b^2-4*a*c the roots are

  • Real and unequal if D>0
  • Real and equal id D=0
  • Imaginary and unequal if D<0

To calculate the roots we simply put the values of coefficients in the formula given and calculate two values using + and – between –b and D =(squareroot(b^2-4*a*c))

Here are the program codes to Solve Quadratic Equation.

Java Code

import java.io.*;    
import java.lang.Math; 
import java.lang.String;
public class QuadEq
{
    void CalRoot(int a, int b, int c )
    {
        double  root1=0.0, root2=0.0; 
		//initialise empty string for storing quadratic equation
		String str="";
		//calculate roots
		root1= (int)(-b+Math.sqrt(b*b-4*a*c))/(2*a);
		root2= (int)(-b-Math.sqrt(b*b-4*a*c))/(2*a);
        //create the string of quadratic equation
		str=String.valueOf(a)+"X^2";
		if (b<0)
			str=str+String.valueOf(b)+"X^1";
		else
			str=str+"+"+String.valueOf(b)+"X^1";
		if (c<0)
			str=str+String.valueOf(c)+"X^0";
		else
			str=str+"+"+String.valueOf(c)+"X^0";	
		//display equation and roots
		System.out.println("\nThe Quadratic Equation "+str); 
		System.out.println("Root 1="+(int)root1);
		System.out.println("Root 2="+(int)root2);
	}

public static void main(String args[]) 
{ 
        //initialise variables
		int a=1, b=3, c=-10;
		// declare object
		QuadEq qe = new QuadEq();
		//call the object method
		qe.CalRoot(a,b,c);
    } 
}
Java code

C Code

#include<stdio.h>
#include<stdlib.h>
#include<math.h>

main()
{
    //Variable declaration
	int a,b,c, root1, root2;
	//Read the Coeffiecients of Quadratic Equation from user
    printf("\nEnter a the Coefficient of X^2  : ");
    scanf("%d",&a);
    printf("\nEnter b the Coefficient of X^1 : ");
    scanf("%d",&b);
    printf("\nEnter c the Coefficient of X^0 : ");
    scanf("%d",&c);
    //Calculate Roots
    root1= (-b+sqrt(b*b-4*a*c))/(2*a);
    root2= (-b-sqrt(b*b-4*a*c))/(2*a);
    // Display quadratic equantion as string
    printf("\nThe Quadratic Equation %dX^2",a); 
    if (b<0)
    	printf("%dX^1",b);
    else
		printf("+%dX^1",b);
	if (c<0)
    	printf("%dX^0\n",c);
    else
		printf("+%dX^1\n",c);	
	// Print Calculated Roots	
    printf("Root 1=%d\n",root1);
    printf("Root 2=%d\n",root2);
}
C code

Python Code

import math
#Input quadratic equation coefficients
a=int(input("Enter a the Coefficient of X^2  : "))
b=int(input("Enter b the Coefficient of X^1 : "))
c=int(input("Enter c the Coefficient of X^0 : "))
try:
    #calculate roots
    root1= (-b+math.sqrt(b*b-4*a*c))/(2*a)
    root2= (-b-math.sqrt(b*b-4*a*c))/(2*a)
    #display Quadratic equation
    qe=str(a)+"X^2"
    if (b<0):
        qe=qe+str(b)+"X^1"
    else:
        qe=qe+"+"+str(b)+"X^1"
    if (c<0):
        qe=qe+str(c)+"X^0"
    else:
        qe=qe+"+"+str(c)+"X^0"
    #display equation and roots
    print("\nThe Quadratic Equation ",qe, " have:")		
    print("Root 1=",int(root1))
    print("Root 2=",int(root2))
except ValueError:
    print("Roots cannot be calculated due to wrong coefficients")
Python code roots of Quadratic Equation