解方程组(x+y)/4-(2x-y)/3=-1 ① 6(x+y)-4(2x-y)=16 ②

来源：学生作业帮助网编辑：作业帮时间：2024/05/09 19:47:21

解方程组(x+y)/4-(2x-y)/3=-1 ① 6(x+y)-4(2x-y)=16 ②
解方程组(x+y)/4-(2x-y)/3=-1 ① 6(x+y)-4(2x-y)=16 ②

解方程组(x+y)/4-(2x-y)/3=-1 ① 6(x+y)-4(2x-y)=16 ②
(x+y)/4-(2x-y)/3=-1 ------------------------(1)
6(x+y)-4(2x-y)=16 ------------------------(2)
转换设x+y=A, 2x-y=B, 则转换后的是：
A/4-B/3=-1 ----------------------------(3)
6A-4B=16 ----------------------------(4)
(3)*12 得： 3A-4B=-12 --------------(5)
(4)-(5) 得： 3A=28; A=28/3
(4)-2*(5) 得： 4B=40, B=10
则： x+y=28/3 ------------------------------(6)
2x-y=10 ------------------------------(7)
(6)+(7) 得： 3x=58/3, x=58/9
y=2x-10=26/9
x=58/9, y= 26/9

(x+y)/4-(2x-y)/3=-1 ①通分得3（x+y）-4（2x-y）=-12整理得（3）-5x+7y=-12
6(x+y)-4(2x-y)=16 ②整理后得(4)-x+5y=8--两边同时×5，得（5）-5x+25y=40
(3)和（5）相减
18y=52
y=26/9 代入到（4）
x=5y-8=5*26/9-8=58/9

解方程组3x+5(x+y)=2 3y-2(x+y)=4 解方程组｛ 3x-4y(x-y)=3 { 2x-3y=1 解方程组x+y/3=x-y/4 2x+3y=11 解方程组,x+y/2=3x-2y=10+6x+y/4, 解方程组2(x-y)/3-x+y/4=-1 6(x-y)-4(2x-y)=16 解方程组：2(x-y)/3-x+y/4=-1 ,6(x+y)-4(2x-y)=16 解方程组:2(x +y)-3(x-y)=3;4(x+ y)+ 3（x-y）=15 解方程组 4(x+y)-(2x-y)=14 ,3(x+y)-2(2x-y)=8 解二元一次方程组3(x+y)-4(x-y)=4 x+y/2+x-y/6=1 解方程组3(x+y)-4(x-y)=4和(x+y)/2+(x-y)/6=1kkkkkkkk 3(x+y)—4(x-y)=4,(x+y/2)+(x-y/6)=1.解方程组解方程组3(x+y)-4(x-y)=4,x+y除以2+x-y除以6=1 解方程组⑴(x+y)/2-(x-y)/3=6,⑵3(x+y)=4(x-y) 解方程组 x-y/3-x+y/4=2 x-y/6-x+y/8=3 解方程组;x+y/2=x-y/3=6 4(x+y)-3(x-y)=-20 解方程组4（x+y)-3(x-y)=14;(x+y)/2+(x+y)/3=6 解方程组 X+Y/2+X-Y/3=6 4[X+Y]-5[X-Y]=2 解二元一次方程组{x+y/2+x-y/3=6,4(x+y)-2=5(x-y)