(y+18)/7x=(y-18)/4x这道方程怎么解?

解方程组24/(x+y) +24/(x-y) = 7/3 ,8/(x+y) +18/(x-y) = 4/3 x-4y+z=-302x+y-z=18x--y-z=7 若7x+6(x-y)=-4,3x-4(y-x)=18,则x-y=__ 3x-y+x=3 4【X-y-1】=3【1-y】-1 5x-4y+4x=3 2x+y-3x=11 【 x除以2 】-【y 除以3】 =2 2x+7y-3x=19 x+y+x=12 3x+2y-x=18 7x:4y,x:y=( ):( (y+18)/7x=(y-18)/4x这道方程怎么解? 解二元一次方程{5X-2y=3 X+6y=7 {5x+4y=-3 2x-3y=8 {x+Y+Z=26 x-Y=1 2x-Y+z =18{x/3+Y/5=3 X/2- 2Y/5=1 快 1 .{5X-2y=3 X+6y=7 2.{5x+4y=-3 2x-3y=8 3.{x+Y+Z=26 x-Y=1 2x-Y+z =18 4.{x/3+Y/5=3 X/2- 2Y/5=1 17.3x+8y=51 x+6y=27 18.9x+3y=99 4x+7y=95 19.9x+2y=38 3x+6y=18 20.5x+5y=45 7x+9y=69 21.8x+2y=28 7x+8y 5x+7y=7x+5y+18 x+2.5-y=7-y 求未知数X y+x+13.2=18+y 求未知数X 18(x+y)^8(x-y)^7÷[3(x+y)^3(x-y)^3]^2 方程题4道1.4(x-y-1)=3(1-y)+3.5 (x/2)+(y/3)=2 2.2(x-y)/3-(x+y)/4=13/6 6(x+y)-4(2x-y)=16 3.3x-y+z=3 2x+y-3z=9 x+y+z=12 4.5x-4y+4z=13 2x+7y-3z=19 3x+2y-z=18 3y=18-5x 3x=4+5y 求x,y 2x-1-3(y-2)=x 2(x-1)-y=4y-18, 2x-1-3(y-2)=x 2(x-1)-y=4y-18, (1)7x+3y=18 2x+3y=13 (2)5x+2y=7 2x+y=1 (3)3x+4y=5 4x+5y=6如题 三元一次方程组 1.3x-y=5 x+2y+z=4 2x+3y-2z=-2 2.x-4y+z=3 2x+y-z=18 x-y-z=7 7X+8Y=4 14X+18Y=8 问X和Y等于几?