We are given the equation $4^{5-9x} = \frac{1}{8^{x-2}}$ and need to solve for $x$.

AlgebraExponentsEquationsSolving EquationsAlgebraic Manipulation
2025/6/5

1. Problem Description

We are given the equation 459x=18x24^{5-9x} = \frac{1}{8^{x-2}} and need to solve for xx.

2. Solution Steps

First, rewrite both sides of the equation using base 2:
4=224 = 2^2 and 8=238 = 2^3.
Substitute these into the equation:
(22)59x=1(23)x2(2^2)^{5-9x} = \frac{1}{(2^3)^{x-2}}
Using the power of a power rule, (am)n=amn(a^m)^n = a^{mn}, we get:
22(59x)=123(x2)2^{2(5-9x)} = \frac{1}{2^{3(x-2)}}
Using the property 1an=an\frac{1}{a^n} = a^{-n}, we have:
22(59x)=23(x2)2^{2(5-9x)} = 2^{-3(x-2)}
Since the bases are equal, we can equate the exponents:
2(59x)=3(x2)2(5-9x) = -3(x-2)
Expand both sides:
1018x=3x+610 - 18x = -3x + 6
Add 18x18x to both sides:
10=15x+610 = 15x + 6
Subtract 6 from both sides:
4=15x4 = 15x
Divide by 15:
x=415x = \frac{4}{15}

3. Final Answer

x=415x = \frac{4}{15}

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