x+3y/2=3/5 5(x-2y)=-4

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x+3y/2=3/5 5(x-2y)=-4
x+3y/2=3/5 5(x-2y)=-4

x+3y/2=3/5 5(x-2y)=-4
小狗·LOVE
x+3y/2=3/5
5(x-2y)=-4
整理,得
10x+15y=6 ①
x-2y=-4/5 ②
②×10,得
10x-20y=-8③
①-③,得
35y=14
解得y=2/5
把y=2/7代入②中,得
x-2×(2/5)=-4/5
x-4/5=-4/5
x=4/5-4/5
x=0
∴此二元一次方程组的解是：x=0,y=2/5

因为x+3y/2=3/5 ,所以x=3/5-3y/2
代入5(x-2y)=-4 ,得:5(3/5-3y/2-2y)=-4
化简得:3-(35/2)y=-4
y=2/5
又因为x=3/5-3y/2
所以 x=0
y=2/5

x=6/5,y=1

式①*10
10x+15y=6③
式②
5x-10y=－4
式②*2
10x-20y=－8④
③－④
35y=14
y=2/5 x=0

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