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9^(2x) • 27^(3-x) = 1/9

User Chobeat
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1 Answer

2 votes

Answer:


\huge\boxed{x=-11}

Explanation:


9^(2x)\cdot27^(3-x)=(1)/(9)\\\\9=3^2;\ 27=3^3;\ (1)/(9)=3^(-2)\\\\\text{therefore}\\\\(3^2)^(2x)\cdot(3^3)^(3-x)=3^(-2)\qquad|\text{use}\ (a^n)^m=a^(nm)\\\\3^(2\cdot2x)\cdot3^(3(3-x))=3^(-2)\\\\3^(4x)\cdot3^(9-3x)=3^(-2)\qquad|\text{use}\ a^n\cdot a^m=a^(n+m)\\\\3^(4x+9-3x)=3^(-2)\\\\3^(x+9)=3^(-2)\iff x+9=-2\qquad|\text{subtract 9 from both sides}\\\\x+9-9=-2-9\\\\x=-11

User Karuppiah RK
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