\(\left(\dfrac{9}{4}\right)^{x-6}=\left(\dfrac{27}{8}\right)^{x-2}\)
\(\Leftrightarrow\left[\left(\dfrac{3}{2}\right)^2\right]^{x-6}=\left[\left(\dfrac{3}{2}\right)^3\right]^{x-2}\)
\(\Leftrightarrow\left(\dfrac{3}{2}\right)^{2x-12}=\left(\dfrac{3}{2}\right)^{3x-6}\)
\(\Leftrightarrow2x-12=3x-6\)
\(\Leftrightarrow-12+6=3x-2x\)
\(\Leftrightarrow x=-6\)
Vậy ............
P/S : Lần sau gỗ bằng công thức toán nhs bn :)