Java Code for Quadratic Equation Solver

<!-- Paste this code into an external JavaScript file named: quadEquation.js --> var a,b,c,x1,x2; function getValues() { signB = (document.form.firstSign.value == "+") ? 1 : -1; signC = (document.form.secondSign.value == "+") ? 1 : -1; a = document.form.x2Coef.value; b = document.form.xCoef.value * signB; c = document.form.endValue.value * signC; } function solveForX() { x1 = ((-1*b) + Math.sqrt((b*b) - 4*a*c))/ (2*a); x2 = ((-1*b) - Math.sqrt((b*b) - 4*a*c))/ (2*a); if(document.form.round.checked){ x1 = Math.round(x1*1000)/1000; x2 = Math.round(x2*1000)/1000; } } function factorEq() { if( (Boolean(x1) != false) && (Boolean(x2) != false)) { x1Print = ((x1 * -1) > 0) ? "+" + (x1*-1) : x1 * -1; x2Print = ((x2 * -1) > 0) ? "+" + (x2*-1) : x2 * -1; aPrint = (a > 1 || a < 0) ? a : ""; document.getElementById('testing').innerHTML = "<font color=\"red\">The Solutions Are:</font><br>x1 = " + x1 + "; x2 = " + x2 + "<br><font color=\"red\"> The Equation Is:</font><br> " + aPrint + "(x " + x1Print + ") (x " + x2Print + ")"; } else { document.getElementById('testing').innerHTML = "<font color=\"red\"><b>YOUR INPUT PRODUCED AN ERROR:</b></font><br> You have entered a non-integer into one of the fields above, or the solution(s) for your equation is(are) an imaginary(s) number!"; } } function SolveEq() { getValues(); solveForX(); factorEq(); }

<!-- Paste this code into the HEAD section of your HTML document. You may need to change the path of the file. --> <script type="text/javascript" src="quadEquation.js"></script>

<!-- Paste this code into the BODY section of your HTML document --> <div align="center"> <form name="form"> <input type="text" name="x2Coef" size="2" value="1"><b> X<sup>2</sup> </b> <select name="firstSign"> <option value="+">+</option> <option value="-">-</option> </select> <input typle="text" name="xCoef" size="2" value="1"><b> X</b> <select name="secondSign"> <option value="+">+</option> <option value="-">-</option> </select> <input type="text" name="endValue" size="2"><br> Round to the nearest thousandths?<input type="checkbox" name="round">Yes<br><br> <input type="button" value="Solve!" onClick="SolveEq()"> </form> <p id="testing" style="width: 400px; height: 100px; border-width: 2px; border-style: groove; border-color: orange; font-size: 16px; color: blue; vertical-align: center">The Solution Will Appear Here!</p> </div> <p><div align="center"> <font face="arial, helvetica" size"-2">Free JavaScripts provided<br> by <a href="http://javascriptsource.com">The JavaScript Source</a></font> </div><p>

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