Answers

2016-01-23T11:55:15+08:00
It is a number used to multiply in a certain variable.

Examples:
9x = 9 is the coefficient
   9x means: 9 multiplied to a number (the unknown number is represented by x)

2x = 2 is the coefficient
   2x means: 2 multiplied to a certain number.

:)
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2016-01-27T17:49:49+08:00
Just think that the coefficient are all numbers
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