Find the value of x in each of the following.
(i) $\sqrt[5]{5 x+2}=2$
(ii) $\sqrt[3]{3 x-2}=4$
(iii) $\left(\frac{3}{4}\right)^{3}\left(\frac{4}{3}\right)^{-7}=\left(\frac{3}{4}\right)^{2 x}$
(iv) $5^{x-3} \times 3^{2 x-8}=225$
(v) $\frac{3^{3 x} \cdot 3^{2 x}}{3^{x}}=\sqrt[4]{3^{20}}$
(i) $\sqrt[5]{5 x+2}=2$
$\Rightarrow(5 x+2)^{\frac{1}{5}}=2$
$\Rightarrow\left[(5 x+2)^{\frac{1}{5}}\right]^{5}=(2)^{5}$
$\Rightarrow(5 x+2)=32$
$\Rightarrow 5 x=32-2$
$\Rightarrow 5 x=30$
$\Rightarrow x=\frac{30}{5}$
$\Rightarrow x=6$
Hence, the value of x is 6.
(ii) $\sqrt[3]{3 x-2}=4$
$\Rightarrow(3 x-2)^{\frac{1}{3}}=4$
$\Rightarrow\left[(3 x-2)^{\frac{1}{3}}\right]^{3}=(4)^{3}$
$\Rightarrow(3 x-2)=64$
$\Rightarrow 3 x=64+2$
$\Rightarrow 3 x=66$
$\Rightarrow x=\frac{66}{3}$
$\Rightarrow x=22$
Hence, the value of x is 22
(iii) $\left(\frac{3}{4}\right)^{3}\left(\frac{4}{3}\right)^{-7}=\left(\frac{3}{4}\right)^{2 x}$
$\Rightarrow\left(\frac{3}{4}\right)^{3}\left(\frac{3}{4}\right)^{7}=\left(\frac{3}{4}\right)^{2 x}$
$\Rightarrow\left(\frac{3}{4}\right)^{3+7}=\left(\frac{3}{4}\right)^{2 x}$
$\Rightarrow\left(\frac{3}{4}\right)^{10}=\left(\frac{3}{4}\right)^{2 x}$
$\Rightarrow 10=2 x$
$\Rightarrow \frac{10}{2}=x$
$\Rightarrow 5=x$
Hence, the value of x is 5.
(iv) $5^{x-3} \times 3^{2 x-8}=225$
$\Rightarrow 5^{x-3} \times 3^{2 x-8}=(15)^{2}$
$\Rightarrow 5^{x-3} \times 3^{2 x-8}=5^{2} \times 3^{2}$
$\Rightarrow x-3=2$ and $2 x-8=2$
$\Rightarrow x=2+3$ and $2 x=2+8$
$\Rightarrow x=5$ and $2 x=10$
$\Rightarrow x=5$ and $x=\frac{10}{2}$
$\Rightarrow x=5$ and $x=5$
$\Rightarrow x=5$
Hence, the value of x is 5.
(v) $\frac{3^{3 x} \cdot 3^{2 x}}{3^{x}}=\sqrt[4]{3^{20}}$
$\Rightarrow \frac{3^{3 x+2 x}}{3^{x}}=\left(3^{20}\right)^{\frac{1}{4}}$
$\Rightarrow \frac{3^{5 x}}{3^{x}}=3^{5}$
$\Rightarrow 3^{5 x-x}=3^{5}$
$\Rightarrow 3^{4 x}=3^{5}$
$\Rightarrow 4 x=5$
$\Rightarrow x=\frac{5}{4}$
Hence, the value of $x$ is $\frac{5}{4}$.