The mathematical word describing both 27x and 6x in the expression is "addition" or "sum"
The mathematical expression is 27x + 6x.
Mathematical expression are combinations of numbers and variables ordered with operations.
Mathematical expression is a combination of numbers, variables, operators (such as addition, subtraction, multiplication or division etc.).
For the given case, the terms are 27x and 6x and the expression formed from them is 27x + 6x.
This simply implies both terms are summed together to give the expression 27x + 6x.
Therefore, the mathematical word describing both 27x and 6x in the expression is "addition" or "sum"
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