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For what value of a does 9 = (StartFraction 1 Over 27 EndFraction) Superscript a + 3?

Negative eleven-thirds
Negative seven-thirds
Seven-thirds
Eleven-thirds

User Kande
by
7.5k points

2 Answers

4 votes

Answer:

A. -11/3

Explanation:

:)

User Kemp
by
7.5k points
3 votes

Answer:


a=-(11)/(3)

Explanation:

We want to find the value of
a for which
9=((1)/(27))^(a+3).

We rewrite with a base of 3 to get:


3^2=((1)/(3^3))^(a+3).

Recall that:
(1)/(a^n)=a^(-n)


\implies 3^2=3^(-3(a+3)).

We now equate the exponents to get:


2=-3(a+3)


2=-3a-9


2+9=-3a


11=-3a


a=-(11)/(3)

The first choice is correct

User Jason Holloway
by
7.7k points