5y-9=7y-13.
8y-4=12-5y+9y
用代入法 1,x-y=4 4x+2y=-1 2,x-y=13 x=6y-7 3,5x-y=110 9y-x=110
解方程:9-3y=5y+5.
y-x=3 7x+5y=-9
(2y-3)(-y+4)=(y-2)(y-5)-3y(y-7/3)解方程
{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
(3y-1)/4-1=(5y-7)/6 9y-3-3=10y-14 9y-10y=-14+3+3 -y=-8 y=8
4x+9y=12 3y-2y+5z=11 5x-6y+7z=13
解方程组: {3x+2y=13 3x-2y=5 {x-y/3=x+y/2+1 2x-5y=9
那6X+5Y=31 2X+3Y=17 6x-2y+y-y=13-7?
3x+2=y 5X+4=Y 7X+6=Y 9X+8=y 11x=y要如何计算