Question

2^3 x 2^n = 2^9
Work out the value of n

Answer 1

Divide both sides by 2³. Remember, when dividing exponent terms with the same base, you subtract the exponents. 

You're then left with $2^{n}$ = $2^{6}$

Therefore, n = 6

Answer 2

$2^{3} + 2^{n} = 2^{9}$
$8 + 2^{n} = 512$
$- 8$    $- 8$
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$2^{n}) = 504$
$ln(2^{x}) = ln(504)$
$xln(2) = ln(504)$
$x = \frac{ln(504)}{ln(2)}$