1.2x+9y=34 2.9x+4y
二元一次方程组试题1.2x+9y=81 3x+y=34 2.9x+4y=35 8x+3y=30 3.7x+2y=52 7
{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
9y=3x-(x-1),4(x+y)-(2x+4)=8y
已知X.x+y.y-4x+2y+5=0,求4X.X-12X Y+9Y.y的值
y=(x+4)(x+9)/x (x>0)
4X+5Y=34 5X+4Y
4x+5y=34 5x+4y=65 则x+y= x-y=多少
很多很多数学题都是求x,y的1.2x-y=5 3x+4y=22.5x-y=110 9y-x=1103.8x+3y=7 5
解方程组{4/x+y+6/x-y=3, 9/x-y-1/x+y=1
解方程组:{4/x+y+6/x-y=3 9/x-y-1/x+y=1}
x>0 y>0 x+y=1,4/X+9/y最小值