However, when trying to find a general solution for the unknown variables in these equations, we're faced with a mathematical constraint: for each unknown, there must be at least one equation that independently describes it.

然而，当试图为这些方程中的未知变量寻找通解时，我们面临着一个数学约束：对于每个未知变量，必须至少有一个独立描述它的方程。