7x+6y=335x-4y=7
若(x-y)/(x+y)=3 则(x+2y)/(6x-7y)等于
4x-(2x+y+16)/2=-6y 2x+3y=7-x-2y
若2x-3y+4=0则x(x*x-1)+x(5-x*x)-6y+7
3x+2=y 5X+4=Y 7X+6=Y 9X+8=y 11x=y要如何计算
3x+2=y 5x+4=y 7x+6=y 9x+8=y 11x=y
y-3x=2,y-5x=4,y-7x=6,y-9x=8,y-11x=0方程组,
3x+2=y 5x+4=y 7x+6=y 9x+8=y 11x=y 联立方程 有的话
化简求值:(7x-2y)(3x-2y-1)-(4x+3y)(9x+6y),其中x=2,y=-1
例X=1 y=21.X+Y=5 X-Y=15 2.2X+3Y=4 5X+6Y=7 3.X+3Y=5 3X+Y=-1 4.
{3x-2y=3,2x+2y=17 {4x-2y=14,5x+y=7 {x+3y=6,2x-3y=3 {2x+3y=11
2X+Y+Z=10,X+2Y+Z=-6,X+Y+2Z=8 5X+4Y-3Y=13,2X-3Y+7Z=19,3X-Y=2X
1.x+x+x+y+y=6.4 y+y+y+x+x=7.1 x= ( ) y=( ) 2.1,4,7,10,13……这串