How do you use an exponent to represent a number such as 16?

You use exponents to represent numbers cause its a different way to display it. To find the exponent that will fit 16 we need to square 16.

√16 = 4

4² =  4 × 4 = 16 

4² = 16.

Hope i helped ya!! 
 

The first one, i believe, would be correct. all the others have one thing in common, and that's that they have repeating numbers. in the second one, x and y have repeating 6's and 3's, and in the third, x and y have repeating 6's as well. in the last one, there are repeating 3's. the first one has no repeating numbers.

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