<script type="text/javascript">
        var a, b, c, x1, x2;
        a = parseFloat(window.prompt("enter a"));
        b = parseFloat(window.prompt("enter b"));
        c = parseFloat(window.prompt("enter c"));
        x1 = (((-1)*(b)) + (Math.sqrt(Math.pow(b,2)) - ((4) * (a) * (c)))) / (2*(a))
        x2 = (((-1)*(b)) - (Math.sqrt(Math.pow(b,2)) - ((4) * (a) * (c)))) / (2*(a))
        if (a == 0 ) document.write("error! a cannot be 0!");
        else document.write("x1 = " + x1 + <br /> + "x2 = " + x2);
    </script>