请用代入法解:{y+1=2(x+2) 2x-3y=1 {y=1-x 5x+2y=8 请利用请用代入法解:{y+1=2(x+2) 2x-3y=1{y=1-x 5x+2y=8请利用整体代入法解:{(x-3)/2-3y=0 2(x-3)-11=2y解二元一次方程组:{5x-6y=11 8x-9y=13{(y+1)/4=
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![请用代入法解:{y+1=2(x+2) 2x-3y=1 {y=1-x 5x+2y=8 请利用请用代入法解:{y+1=2(x+2) 2x-3y=1{y=1-x 5x+2y=8请利用整体代入法解:{(x-3)/2-3y=0 2(x-3)-11=2y解二元一次方程组:{5x-6y=11 8x-9y=13{(y+1)/4=](/uploads/image/z/14060230-70-0.jpg?t=%E8%AF%B7%E7%94%A8%E4%BB%A3%E5%85%A5%E6%B3%95%E8%A7%A3%EF%BC%9A%7By%2B1%3D2%EF%BC%88x%2B2%EF%BC%89+2x-3y%3D1+%7By%3D1-x+5x%2B2y%3D8+%E8%AF%B7%E5%88%A9%E7%94%A8%E8%AF%B7%E7%94%A8%E4%BB%A3%E5%85%A5%E6%B3%95%E8%A7%A3%EF%BC%9A%7By%2B1%3D2%EF%BC%88x%2B2%EF%BC%89+2x-3y%3D1%7By%3D1-x+5x%2B2y%3D8%E8%AF%B7%E5%88%A9%E7%94%A8%E6%95%B4%E4%BD%93%E4%BB%A3%E5%85%A5%E6%B3%95%E8%A7%A3%EF%BC%9A%7B%EF%BC%88x-3%EF%BC%89%2F2-3y%3D0+2%EF%BC%88x-3%EF%BC%89-11%3D2y%E8%A7%A3%E4%BA%8C%E5%85%83%E4%B8%80%E6%AC%A1%E6%96%B9%E7%A8%8B%E7%BB%84%EF%BC%9A%7B5x-6y%3D11+8x-9y%3D13%7B%EF%BC%88y%2B1%EF%BC%89%2F4%3D)
请用代入法解:{y+1=2(x+2) 2x-3y=1 {y=1-x 5x+2y=8 请利用请用代入法解:{y+1=2(x+2) 2x-3y=1{y=1-x 5x+2y=8请利用整体代入法解:{(x-3)/2-3y=0 2(x-3)-11=2y解二元一次方程组:{5x-6y=11 8x-9y=13{(y+1)/4=
请用代入法解:{y+1=2(x+2) 2x-3y=1 {y=1-x 5x+2y=8 请利用
请用代入法解:
{y+1=2(x+2) 2x-3y=1
{y=1-x 5x+2y=8
请利用整体代入法解:
{(x-3)/2-3y=0 2(x-3)-11=2y
解二元一次方程组:
{5x-6y=11 8x-9y=13
{(y+1)/4=(x+2)/3 2x-3y=1
请用代入法解:{y+1=2(x+2) 2x-3y=1 {y=1-x 5x+2y=8 请利用请用代入法解:{y+1=2(x+2) 2x-3y=1{y=1-x 5x+2y=8请利用整体代入法解:{(x-3)/2-3y=0 2(x-3)-11=2y解二元一次方程组:{5x-6y=11 8x-9y=13{(y+1)/4=
代入法求解
1、∵ y+1=2(x+2)
∴ y=2(x+2)-1
代入2x-3y=1,得2x-3[2(x+2)-1]=1 解得 x=2 y=1
2、将y=1-x 代入方程二,得 5x+2(1-x)=8 解得 x=2 y=-1
整体代入法求解
3、∵(x-3)/2-3y=0
∴ (x-3)=6y 代入 2(x-3)-11=2y
得2*6y-11=2y
解得y=1.1 x=9.6
解二元一次方程组:
5x-6y=11 ①
8x-9y=13 ② 由两式联立消去y ①*3- ②*2得 -x=7 得x=-7 y=-23/3
(y+1)/4=(x+2)/3 ①
2x-3y=1 ② 由②式得 x=(1+3y) /2 代入 (y+1)/4=(x+2)/3
得 (y+1)/4=[(1+3y) /2+2]/3 解得 y=-7/3 x=-3