hypot()

hypot() is a PHP native function, that computes the length of the hypotenuse on a right triangle, given the length of the two other sides.

hypot() is the same as calculating sqrt(pow($a, 2) + pow($b, 2)) or sqrt($a ** 2 + $b ** 2). It is also the length of a segment from the origin to a point of coordinates ($a, $b).

<?php

    $x = 3;
    $y = 4;
    var_dump(hypot($x, $y));

?>

Documentation

Related : Exponent, sqrt()