<?php
$a = 1;
$b = -3;
$c = -4;



     $delta = ($b*$b)-4*($a*$c);
		 echo ("delta = $delta");

					echo "</br>";

	$x1=(-$b-sqrt($delta)) / (2*$a);
		echo ("x1 = $x1");

					echo "</br>";

	$x2=(-$b+sqrt($delta)) / (2*$a);
		echo ("x2 = $x2");

?>