Tag Archive : Python Program to Solve Quadratic Equation

Quadratic Equation Code in Python

Introduction:

In this article, I am going to explain how to find the solutions for the quadratic equation with the Python code. Please install python 3.8 from the link given below to run this code.
https://www.python.org/downloads/

I prefer you to use atom text editor to type your code or to save the given code:
https://atom.io/

You can download the the Quadratic Equation.py from GitHub using the given link:

Link for the code in GitHub

Code:

#Quadratic equation
a=int(input())
b=int(input())
c=int(input())

d_d = b**2-(4*a*c) #Assigning variables to make the program simpler
d = d_d**(1/2)  #Root of b square -4ac
sol1 = ((-b)+d)/(2*a)
sol2 = ((-b)-d)/(2*a)

#Check if solution exists

if d_d < 0:
   print('Solution exists in complex numbers')

#Return the solution if it exists in real numbers) 
else:
   print('x = {0} or x = {1}'.format(sol1,sol2))  

Example Input:

1
2
1

Output:

x = -1.0 or x = -1.0

Code Explanation:

In this code, what we basically do is that, we get the 3 inputs from the user which are the values of a,b and c in a quadratic equation of the form ax2+bx+c.

Quadratic Equation in Python
Quadratic Equation

Code (Assignings):

  • The variable d_d is assigned the value of b2-4ac.
  • The variable d is assigned the value of root of d_d, that is root of b2-4ac.
  • Since an equation has 2 values ( ± ).
  • The value when used ‘+’ is assigned to the variable sol1.
  • Similarly, the value when used ‘-‘ is assigned to the variable sol2.

Code(If…Else):

  • In a quadratic equation when the value of b2-4ac is less than 0, then solution is in complex numbers.
  • In order to test this, we are checking whether d_d is less than 0 or not.
  • If less than 0, the ‘if’ statement is executed where the string (‘Solution exists in complex numbers’) is executed. If not then the real number value is executed (else statement)

Conclusion:

The above article explains the solution to quadratic equation using python coding. If you have any questions or feedback on this, feel free to post in the comments section below.