How to enter the solution:

If the value of a variable is a number, just enter the number.

If the value of a variable is a formula involving free variables, enter the formula. For example, if you obtain that $x_1=1-2x_2+3x_3$

where $x_2$ and $x_3$ are free, then as the value of $x_1$ you should enter $1-2**x_2+3**x_3.$ Use the underscore $\_$ to indicate

subscripts of variables, and $*$ to indicate multiplication.

If a variable is a free variable, enter the variable name as its value. For example, if $x_2$ is a free variable, then you should enter x$\_2$ as

the value of $x_2.$

If the system has no solutions enter None as the value of one of the variables. In such case you can leave values of the remaining

variables blank.