Answer :
Given:
The equation is
[tex]\left(\dfrac{3}{5}\right)^x\left(\dfrac{5}{3}\right)^{2x}=\dfrac{125}{27}[/tex]
To find:
The value of x.
Solution:
We have,
[tex]\left(\dfrac{3}{5}\right)^x\left(\dfrac{5}{3}\right)^{2x}=\dfrac{125}{27}[/tex]
[tex]\left(\dfrac{5}{3}\right)^{-x}\left(\dfrac{5}{3}\right)^{2x}=\dfrac{5\times 5\times 5}{3\times 3\times 3}[/tex] [tex][\because \left(\dfrac{a}{b}\right)^{-m}=\left(\dfrac{b}{a}\right)^{m}][/tex]
[tex]\left(\dfrac{5}{3}\right)^{-x+2x}=\dfrac{5^3}{3^3}[/tex] [tex][\because a^ma^n=a^{m+n}][/tex]
[tex]\left(\dfrac{5}{3}\right)^{x}=\left(\dfrac{5}{3}\right)^{3}[/tex]
On comparing the exponents, we get
[tex]x=3[/tex]
Therefore, the value of x is 3.