# Check whether one root of the Quadratic Equation is twice of other or not

• Last Updated : 23 Jun, 2021

Given three numbers A, B, C which represents the coefficients(constants) of a quadratic equation , the task is to check whether one root of the equation represented by these constants is twice of other or not.
Examples:

Input: A = 1, B = -3, C = 2
Output: Yes
Explanation:
Its roots are (1, 2).
Input: A = 1, B = -5, C = 6
Output: No
Explanation:
Its roots are (2, 3). or

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Approach: The idea is to use the concept of quadratic roots to solve the problem. We can formulate the condition required to check whether one root is twice of the other or not by:

1. The sum of roots = = 3. This value is equal to:

1. Similarly, the product of the roots = = 2. This value is equal to:

1. We can solve the above two equations and to get the condition:

1. Therefore, inorder for the first assumption of the roots to hold true, the above condition needs to hold true. Hence, we simply check if the above condition is true or not for the given coefficients.

Below is the implementation of the above approach:

## C++

 // C++ program to check if one root// of a Quadratic Equation is// twice of other or not #include using namespace std; // Function to find the required answervoid checkSolution(int a, int b, int c){    if (2 * b * b == 9 * a * c)        cout << "Yes";    else        cout << "No";} // Driver codeint main(){    int a = 1, b = 3, c = 2;     checkSolution(a, b, c);     return 0;}

## Java

 // Java program to check if one root// of a quadratic equation is// twice of other or notclass GFG{ // Function to find the required answerstatic void checkSolution(int a, int b, int c){    if (2 * b * b == 9 * a * c)        System.out.print("Yes");    else        System.out.print("No");} // Driver Codepublic static void main(String[] args){    int a = 1, b = 3, c = 2;     checkSolution(a, b, c);}} // This code is contributed by shubham

## Python3

 # Python3 program to check if one root# of a Quadratic Equation is# twice of other or not # Function to find the required answerdef checkSolution(a, b, c):     if (2 * b * b == 9 * a * c):        print("Yes");    else:        print("No"); # Driver codea = 1; b = 3; c = 2;checkSolution(a, b, c); # This code is contributed by Code_Mech

## Javascript

Output:
Yes

Time Complexity: O(1)

Auxiliary Space: O(1)

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