x/y=9/20 x/(y+16)=1/4 x是多少
x/y=9/20 x/(y+16)=1/4 x是多少
{4/(x+y)+6/(x-y)=3 {9/(x-y)-1/(x+y)=1
已知4x=9y求(1)x+y/y (2)y-x/2x
已知x>0,y>0,9/x+16/y=1,则x+y的最小值是多少?
X=3,Y=4,X=Y,X是多少 Y是多少
9y=3x-(x-1),4(x+y)-(2x+4)=8y
值域y=3x/(x²+x+1)是多少?
如果x+x+x+y+y=54,x+x+y+y=56,那么x和y各是多少?
x+y/2+x-y/3=6,4(x+y)-3(x-y)=-20
{(x+y)/2+(x-y)/3=6 4(x+y)-3(x-y)=-20
4(x+y)-3(x-y)=-20,2/x+y+3/x-y=6
{3(x+y)-4(x-y)=4 {x+y/2 + x-y/6=1