For what value of [tex]\( x \)[/tex] does [tex]\( 3^{4x} = 27^{x-3} \)[/tex]?

A. [tex]\(-9\)[/tex]
B. [tex]\(-3\)[/tex]
C. 3
D. 9



Answer :

To solve the equation [tex]\(3^{4x} = 27^{x-3}\)[/tex], we can follow these steps:

1. Express 27 with base 3:
We know that [tex]\(27\)[/tex] can be written as [tex]\(3^3\)[/tex]. Thus, we can rewrite the equation using a common base:

[tex]\[ 3^{4x} = (3^3)^{x-3} \][/tex]

2. Simplify the right side:
Apply the power of a power property [tex]\(((a^m)^n = a^{m \cdot n})\)[/tex]:

[tex]\[ 3^{4x} = 3^{3(x-3)} \][/tex]

3. Equate the exponents:
Since the bases are the same, we can set the exponents equal to each other:

[tex]\[ 4x = 3(x-3) \][/tex]

4. Solve for [tex]\(x\)[/tex]:
Distribute the [tex]\(3\)[/tex] on the right side:

[tex]\[ 4x = 3x - 9 \][/tex]

Next, isolate [tex]\(x\)[/tex] by subtracting [tex]\(3x\)[/tex] from both sides:

[tex]\[ 4x - 3x = -9 \][/tex]

Simplify the left side:

[tex]\[ x = -9 \][/tex]

So, the value of [tex]\(x\)[/tex] that satisfies [tex]\(3^{4x} = 27^{x-3}\)[/tex] is [tex]\(\boxed{-9}\)[/tex].