3/10x=2/5y y=45,
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3/10x=2/5yy=45,3/10x=2/5yy=45,3/10x=2/5yy=45,把y=45代入3/10x=2/5y得3/10x=2/5·453/10x=18x=60谁说这个解是x=60,y=
3/10x=2/5y y=45,
3/10x=2/5y y=45,
3/10x=2/5y y=45,
把y=45代入3/10x=2/5y
得3/10x=2/5·45
3/10x=18
x=60
谁说这个解是x=60,y=45了？？
x=2/5y 除以3/10
x=2/5y *10/3=4/3y
当y=45时，x=60
第一步：去分母后得 3x=4y x=3/4y
第二步：代入y=45得 x=60
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3/10x=2/5y y=45,
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