Answer:
(−6)²
Explanation:
(−6)⋅(−6)
This means the numbers are being multiplied.
A number is being multiplied by the same number. You can write an exponent for the number of times it's being multiplied by itself.
Example:
x = x¹
x·x = x²
x·x·x = x³
You are multiplying (−6) twice.
(−6)⋅(−6) = (−6)²