In the question: What is 10(x) = ?, what is this x?
x usually is used to denote a variable. A variable can take on different values and you are usually provided with a set of equations or constraints that are used to determine the value of that is appropriate and satisfies the given criteria.
For example, if you have x + 2 = 12, the value of x would be 12 - 2 = 10.
If you have to determine what 10(x) is equal to, you have to multiply the value of x with 10.
The value of 10(x) for the value of x as derived by the equation in the example given earlier is 10*10 = 100
The x in 10(x) is a variable value that is being multiplied by a constant 10.
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