Answer:
Step-by-step explanation:
The properties of addition and multiplication allow you to rearrange and/or regroup the components of a sum or a product. That is the point of this exercise.
(2·8)·7 = 2·(8·7) . . . . parentheses have moved: associative property
2 + 7 + 8 = 8 + 2 + 7 . . . . order is rearranged: commutative property
5·3·12 = 12·5·3 . . . . . order is rearranged: commutative property
(3 +5) +12 = 3 +(5 +12) . . . . parentheses have moved: associative property
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<em>Additional comment</em>
Whenever you're in doubt about the equivalence of numerical expressions, you can use your calculator to evaluate them. They will give the same result if they are equivalent. (You need a good scientific or graphing calculator that uses parentheses for this. Some seriously good calculators are available as low-cost phone apps.)
The Google search box also serves as input to the Google calculator. You can use an asterisk (*) for multiplication.
