5+2X=40用方程解怎样解x=35/25+2X=402X=40-52X=35X=35/

x=35/2

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5+2X=40
2X=40-5
2X=35
X=35/2
X=17.5

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5+2X=40
2X=40-5
2X=35
X=17.5
∴x=17.5

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