3x+5y-2x-7y= x-2y
¬Û¦PÅܶq¤~¥i¥[´î
3x©M-2x p, +5y©M-7yp
3x+5x
2
-2x-7x
2
= x-2x
2
¬Û¦PÅܶq¤Î«ü¼Æ¤~¥i¥[´î
3x©M-2x p, +5x
2
©M-7x
2
p
(3x+5y)-(2x-7y)+(6y-4x)
= 3x+5y -2x+7y +6y-4x = -3x+18y
²¾°£¬A¸¹®É,Y«e±¬°´î,¤ºùØnÅܲŸ¹
ÃD¥Ø
1
2
3
4
5
6
7
¡@¡@§Aªºµª®×
¥¿½Tµª®×
1
2
3
4
5
6
7
p®É