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Solve the exponential equation for 
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{:[27^(5x-4)=81^(7x-2)],[x=◻]:}

Solve the exponential equation for x x .\newline275x4=817x2x= \begin{array}{l} 27^{5 x-4}=81^{7 x-2} \\ x=\square \end{array}

Full solution

Q. Solve the exponential equation for x x .\newline275x4=817x2x= \begin{array}{l} 27^{5 x-4}=81^{7 x-2} \\ x=\square \end{array}
  1. Recognize powers of 33: Recognize that both 2727 and 8181 are powers of 33. 2727 is 333^3 and 8181 is 343^4.\newlineRewrite the equation using the base of 33.\newline275x4=817x227^{5x-4} = 81^{7x-2}\newline(33)5x4=(34)7x2\Rightarrow (3^3)^{5x-4} = (3^4)^{7x-2}
  2. Rewrite equation using base of 33: Apply the power of a power rule, which states that (ab)c=a(bc)(a^b)^c = a^{(b*c)}.$33\$3^3^{(55x4-4)} = 343^4^{(77x2-2)}\)3(3(5x4))=3(4(7x2))\Rightarrow 3^{(3*(5x-4))} = 3^{(4*(7x-2))}
  3. Apply power of a power rule: Simplify the exponents on both sides.\newline33(5x4)=34(7x2)3^{3(5x-4)} = 3^{4(7x-2)}\newline315x12=328x8\Rightarrow 3^{15x-12} = 3^{28x-8}
  4. Simplify exponents: Since the bases are the same, set the exponents equal to each other. 15x12=28x815x - 12 = 28x - 8
  5. Set exponents equal: Solve for xx by first moving the xx terms to one side and the constants to the other side.\newlineSubtract 15x15x from both sides:\newline15x1215x=28x815x15x - 12 - 15x = 28x - 8 - 15x\newline12=13x8\Rightarrow -12 = 13x - 8\newlineAdd 88 to both sides:\newline12+8=13x8+8-12 + 8 = 13x - 8 + 8\newline4=13x\Rightarrow -4 = 13x
  6. Solve for x: Divide both sides by 1313 to solve for x.\newline413=13x13-\frac{4}{13} = \frac{13x}{13}\newlinex=413\Rightarrow x = -\frac{4}{13}

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