A

*VARIABLE*is a letter that represents an*unknown*number.For example,

*x, y, n*are usually represented for an*unknown*number.An

*EXPRESSION*is any single number(3) or variable(x) or combination of operation(+) involving numbers and a variable.For example, 2

*y*-7.The

*VALUE*is a known or calculated amount.For example, 3 is a known or calculated amount.

A

*CONSTANT*is a number that does not change, but it increases or decreases the value of an expression.For example, 3

*x*+5. 5 is the constant.A

*NUMERICAL COEFFICIENT*is a number that multiplies the variable.For example, 10

*x*^{4}. The numerical coefficient is 10.Do you understand now? I sure hope you do.

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