---
id: 5900f3c71000cf542c50feda
challengeType: 5
title: 'Problem 91: Right triangles with integer coordinates'
---
## Description
The points P (x1, y1) and Q (x2, y2) are plotted at integer co-ordinates and are joined to the origin, O(0,0), to form ΔOPQ.
There are exactly fourteen triangles containing a right angle that can be formed when each co-ordinate lies between 0 and 2 inclusive; that is,0 ≤ x1, y1, x2, y2 ≤ 2.
Given that 0 ≤ x1, y1, x2, y2 ≤ 50, how many right triangles can be formed?
## Instructions
## Tests
```yml
tests:
- text: euler91() should return 14234.
testString: assert.strictEqual(euler91(), 14234, 'euler91() should return 14234.');
```
## Challenge Seed
```js
function euler91() {
// Good luck!
return true;
}
euler91();
```