The solution of the first equation is

X =–2 and x =–4;

The solution of the second equation is

X=4 and x =–3;

The solution of the third equation is

X= 1+√3/3，X = 1–√3/3。

The solution is as follows:

Binary linear equation:

It is relatively simple to solve these three equations with addition, subtraction and elimination.

The solution of the first equation group is

x= 1，y = 1；

The solution of the second equation group is

x=3，y = 2；

The solution of the third equation group is

x=2，y= 1 .

The solution is as follows (the method is not unique)