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15 votes
15 votes
Which expression is equivalent to 8^-3 times 8^-9?

a. 1/8^27
b. 8^-12
c. 8^27
d. 1/8^-12

User Liron Achdut
by
2.7k points

1 Answer

20 votes
20 votes

Answer:

B

Explanation:

Multiplying numbers with exponents rule:


{a}^(b) * {a}^(c) = {a}^(b + c)

Explanation of rule: keep the base the same and add the exponents. Keep in mind this rule only works when the base of both numbers are the same.

Applying rule: 8^-3 x 8^-9

keep base as 8 and add the exponents


{8}^( - 3) * {8}^( - 9) = {8}^(( - 3) + ( - 9)) = {8}^( - 12)

b is the answer