用代入法解:2x-y=4 x+3y=9 用加减法解:4x+y=-3 2x-3y=-5
用代入法解:2x-y=4 x+3y=9 用加减法解:4x+y=-3 2x-3y=-5
4X+3Y=5 2x-y=-5用加减法和代入法解
用代入法解:1.3x+2y=1 6x+7y-2=0 2.2x-3y=5 2x+y=3 用加减法解:1.2X+Y=1 3X
用代入法解方程组:y=3(x-y),x=2(x-y)
3x+4y=2,2x-y=5用代入法解
用代入法解方程组:2x+3y=-1 4x-y=5
2x+y=5 4x+3y=11 用整体代入法解
用代入法解方程组:{y=2x-3,3x+2y=8 {2x-y=5,3x+4y=2
用加减法解二元一次方程组 {3x+4y=19 } 要用代入消元法 {x-y=4}
3x+y+17=05y-2x+17=0用代入消元法或代入加减法
用代入法解此方程组:(x+y)/2+(x-y)/3=6 4(x+y)-5(x-y)=2
用代入法解方程组 {x-y=3 2y+3(x-y)=11}