# Math Help - exponential equation

1. ## exponential equation

hey can someone run me through the steps to solve:

2^2x - 2^(x+3) + 2^4 = 0

thanks much appreciated

2. Originally Posted by seanybeaver
hey can someone run me through the steps to solve:

2^2x - 2^(x+3) + 2^4 = 0

thanks much appreciated
$\Rightarrow 2^{2x} - 8 (2^x) + 16 = 0$.

Substitute $w = 2^x$:

$w^2 - 8w + 16 = 0$.

Solve for w. Then solve $2^x = w$ for x.

3. thanks a lot