Answer:
3 square units
Step-by-step explanation:
Put the numbers in the formula and do the arithmetic.
A = 12(1/2)² = 12(1/4) = 3 . . . square units
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Comment on the working
It might be helpful to you to see how this works when the units of the number are attached to the number.
A = 12(1/2 unit)² = 12(1/2 unit)(1/2 unit) = 12(1/2)(1/2)(unit)(unit) = 3 unit²
I often choose to keep the units with the numbers, just to make sure that the numbers and units are correct. For example, you can multiply inches by feet, but you get in·ft, which is not square inches and not square feet. You have to do a conversion to get the result in square units.