解几道较简单的二元一次方程组(1)x/3-y/15=4/3 (2)0.5x+0.8y=4.7 x/4-y/10=4/3 1.2y+0.6x=6.6(3)3x-2y=(x-3y)/5=(2x-1)/4 快呀,(1)x/3-y/15=4/3 x/4-y/10=4/3 (2)0.5x+0.8y=4.7 1.2y+0.6x=6.6 (3)3x-2y=(x-3y)/5=(2x-1)/4怕你们看不清题目,再重新输一遍

问题描述:

解几道较简单的二元一次方程组
(1)x/3-y/15=4/3 (2)0.5x+0.8y=4.7
x/4-y/10=4/3 1.2y+0.6x=6.6
(3)3x-2y=(x-3y)/5=(2x-1)/4 快呀,
(1)x/3-y/15=4/3
x/4-y/10=4/3
(2)0.5x+0.8y=4.7
1.2y+0.6x=6.6
(3)3x-2y=(x-3y)/5=(2x-1)/4
怕你们看不清题目,再重新输一遍

(1)5x-y=20 ----------a
5x-2y=80/3--------b
a-b:y=-20/3
x=8/3
(2) 1.5x+2.4y=14.1 -----------a
1.2x+2.4y=13.2 -----------b
a-b:0.3x=0.9
x=3
y=4
(3)3x-2y=(x-3y)/5
2x=y
所以,3x-2y=(2x-1)/4
3x-4x=(2x-1)/4
-4x =2x-1
x =1/6
y=1/3