7x+9y=59 9x+7y=53
X+Y=9 6X+7Y=59
y-x=3 7x+5y=-9
{y=x+3,7x+5y+9;
x+y=3 x+2y=9 3/x+1=y y-x=3 y=2x-3 y-3x=1 2(x+1)-y=6 7x-5y=-9
7x+9y=59 9x+7y=53解方程
7x+9y=59 9x+7y=53
7x-6y=3 3x+6y=9 x= y=
x-2y=9 x+y+z=7 2x-3y=12
9x-7/y=0(x,y不等于0),x和y,成()比例,为什么?
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,