To rewrite the expression "64 : ?" as a radical raised to a power, we need to determine the square root of 64.
The square root of a number "x" can be written as √x, and it represents a number "y" that, when multiplied by itself, equals "x." In this case, we are looking for a number "y" such that y * y = 64.
The square root of 64 is 8 because 8 * 8 = 64.
So, we can rewrite the expression "64 : ?" as "64 = 8^2."