<?php

// a * a = b * b + c * c
function hipotenusa($b, $c)
{
    $b2 = $b * $b;
    $c2 = $c * $c;
    $a2 = $b2 + $c2;
    $a = sqrt($a2);
    echo $a;
}
hipotenusa(3, 4);
<?php

function hipotenusa($b, $c)
{
    $b2 = $b * $b;
    $c2 = $c * $c;
    $a2 = $b2 + $c2;
    $a = sqrt($a2);
    echo $a;
}
hipotenusa(10, 10);