Реши уравнения 30 + х = 39 39 - х = 9 х - 9 = 30

Question

Реши уравнения
30 + х = 39
39 - х = 9
х - 9 = 30

Answer 1

30+x= 39 
x=39-30
x=9
30+9=39
39=39

Comments

x=39-9

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x=30

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39-30=9

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9=9

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x-9=30

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x=30+9

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x=39

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339-9=30

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39-9=30

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30=30