1.(用代入法)5x-y=110---------①
9y-x=110---------②由②,x=9y-110,③代入①,45y-550-y=110,44y=660,y=15,代入③,x=25.∴{x=25,
{y=15.2.2.加减法(1)m+b=11---------①
-4m-b=11---------②①+②,-3m=22,m=-22/3,代入①,b=55/3. (2)0.6x-0.4y=1.1---------①
0.2x-o.4y=2.3---------②①-②,0.4x=-1.2,x=-3,代入①,-1.8-0.... |