x+18y=288*18 x+30y=180*30 x+5y=5n x=?y=?n=?x+18y=288*18x+30y=180*30x+5y=5n x=?y=?n=?

18x/34y=9/1 x/y=?/? {6/x+y+10/x-y=30 6/x+y-10/x-y=-1 X+y+z=26,x-y=1,2x-y+z=18 2x-1-3(y-2)=x 2(x-1)-y=4y-18, 2x-1-3(y-2)=x 2(x-1)-y=4y-18, 解二元一次方程(1)2x+y=10,x+2y=8.（2）x+y=18,30%x+70%y=18×50（3）x+y=460,43x=44y=20000 x-y/x-x+y/y-(x+y)(x-y)/y² y/x=2 y'/y=1/x 计算题!【x+y+z=26；x-y=1；2x-y+z=18】!【x/3+y/5；x/2-2y/5=1】 328-y/y x 100％=-18％ 化简 x / y(x+y) - y / x(x+y) = 3x-y+x=3 4【X-y-1】=3【1-y】-1 5x-4y+4x=3 2x+y-3x=11 【 x除以2 】-【y 除以3】 =2 2x+7y-3x=19 x+y+x=12 3x+2y-x=18 y'-(1/x)y=xe^-x 100x+10y+1z=18x+18y+18x 求：x、y、z各是几. x(x+y)(x-y)-y(y+x)(y-x)=(x-y)( )填空 X-Y=3(y-2),2(x-1)=5Y-18解下列方程组 x+18y=288*18 x+30y=180*30 x+5y=5n x=?y=?n=?x+18y=288*18x+30y=180*30x+5y=5n x=?y=?n=? y(x+y)+(x-y)²-（x+y）（x-y）,其中x=-1/3,y=3