Question

$4 {}^{x} = 900 what \: is \: the \: value \: of \: {4}^{x - 2 }$

Answer 1

${4}^{x} = 900 \: (given) \: \: - - - (i)$


Now,
${4}^{x - 2} = \frac{ {4}^{x} }{ {4}^{2} } - - - (ii)$


Substitute (i) in (ii)
and you'll end up with,

$\frac{900}{16} = 56.25$