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Check if right triangle possible from given area and hypotenuse

Last Updated : 23 Jul, 2025

Given area and hypotenuse, the aim is to print all sides if right triangle can exist, else print -1. We need to print all sides in ascending order.

Examples: 

Input : 6 5
Output : 3 4 5

Input : 10 6
Output : -1 

We have discussed a solution of this problem in below post. 
Find all sides of a right angled triangle from given hypotenuse and area | Set 1
In this post, a new solution with below logic is discussed.
Let the two unknown sides be a and b 
Area : A = 0.5 * a * b 
Hypotenuse Square : H^2 = a^2 + b^2 
Substituting b, we get H2 = a2 + (4 * A2)/a2 
On re-arranging, we get the equation a4 - (H2)(a2) + 4*(A2)
The discriminant D of this equation would be D = H4 - 16*(A2
If D = 0, then roots are given by the linear equation formula, roots = (-b +- sqrt(D) )/2*a 
these roots would be equal to the square of the sides, finding the square roots would give us the sides. 

Output: 

3 4 5

Time complexity: O(log(n)) since using inbuilt sqrt functions

Auxiliary Space: O(1)


 

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