4.若方程组axby22x3y4与的解相同,求(a+b)的值 axby24x5y6 5.用加减消元法解下列方程 (1)xy3xy1 (4)4xy53x2y1 (7)7m3n12n3m2 (2)3x4y152x4y10 (3)4x3y54x6y145)5x4y6 (6)3x2y72x3y12x3y17x3y5 (8)237,2y3 x4352. ( 6.用适合的方法解下列方程组: (1) 3 x (2) 2y3z4 y 7x2y2 (3) x 2 y 3 7x5y6 (5) 3xy15x4y2 5y6z7(4) 3x5y4 19x 3y63x2y20(6) 3x2y2252x5 本文来源:https://www.wddqw.com/doc/258d9dadb90d4a7302768e9951e79b89680268ec.html