System of Linear Equations

You are given a system of two linear equations in the unknowns $x$ and $y$. Write a program that solves the system.

The first line contains the number of test cases $T$.

Each test case consists of two equations, one per line. Different test cases are separated by a blank line.

In each equation, two or more terms are joined by the operators +, -, and =. Each term is either an integer or a variable ($x$ or $y$); a variable may be preceded by a minus sign and/or a coefficient. The = sign appears exactly once per equation. Every operator is surrounded by spaces, and a single term contains no spaces.

For each test case, print the value of $x$ and then the value of $y$, one per line, as a reduced fraction. If a value is an integer, print just the integer with no denominator.

If the value of a variable is not uniquely determined — that is, the system has no solution, or that variable may take more than one value — print don't know in its place. The two variables are judged independently, so it is possible for one variable to have a fixed value while the other is don't know.

Print a blank line between the outputs of consecutive test cases.