你说的可能是行列式法：
D =丨a b 丨= ae-bd
丨d e 丨
Dx=丨c b 丨= ce-bf
丨f e 丨
Dy=丨a c 丨= af-cd
丨d f 丨
x = Dx/D =(ce-bf)/(ae-bd)
y = Dy/D =(af-cd)/(ae-bd)