Answer:
(c) (-30)⁴
Explanation:
You want to simplify the product (-6)⁴×(5)⁴.
Exponents
An exponent is an indicator of repeated multiplication:
(-6)⁴ = (-6)(-6)(-6)(-6) . . . . . . the factor -6 is repeated 4 times
(5)⁴ = (5)(5)(5)(5)
Then the product is ...
(-6)⁴ × (5)⁴ = (-6)(-6)(-6)(-6)(5)(5)(5)(5)
The commutative and associative properties of multiplication let you regroup this to ...
(-6)(5)×(-6)(5)×(-6)(5)×(-6)(5) = (-30)(-30)(-30)(-30)
Using the exponent to signify repeated multiplication, this can be written as the equivalent ...
(-30)⁴
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Additional comment
This product has an even number of minus signs, so will be positive. It is fully equivalent to ...
30⁴.