假设二元一次方程如下：
x + y = 11
x - y = 5
解方程如下：
1 <!DOCTYPE html>
2 <html lang="zh-CN">
3
4 <head>
5 <meta charset="UTF-8" />
6 <meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1" />
7 <title>测试algebra函数库（解两元一次方程）</title>
8 <script src="js/algebra.min.js"></script>
9 <script type="text/javascript">
10 var Fraction = algebra.Fraction;
11 var Expression = algebra.Expression;
12 var Equation = algebra.Equation;
13 //=======================================
14
15 var x1 = algebra.parse("x+y=11");
16 var answer1 = x1.solveFor("y");
17 //console.log("y = " + answer1.toString());
18
19 var x2 = algebra.parse("x-y=5");
20 var answer2 = x2.solveFor("y");
21 //console.log("y = " + answer2.toString());
22 //=================================================
23 //解出X值
24 var eq = new Equation(answer1, answer2);
25 console.log("x表达式：" + eq.toString());
26 var answerX = eq.solveFor("x");
27 console.log("解出X的值为：" + answerX.toString());
28 //=================================================
29 //解出Y值（把x的值代入x1或x2）
30 eq = x1.eval({
31 x: answerX
32 });
33 console.log("y表达式：" + eq.toString());
34 var answerY = eq.solveFor("y");
35 console.log("解出Y的值为：" + answerY.toString());
36
37 </script>
38 </head>
39
40 <body>
41
42 </body>
43
44 </html>
控制台输出：
x表达式：-x + 11 = x - 5
解出X的值为：8
y表达式：y + 8 = 11
解出Y的值为：3
代码写得很粗旷，无任何包装。看得懂就好。