the 4th option
Step-by-step explanation:
8 = 2ยณ
so, when we convert
![{8}^{x - 3}](/tpl/images/1398/5502/74ae2.png)
into a "2 to the power of" expression, we get therefore
![({2}^{3}) ^{x - 3}](/tpl/images/1398/5502/41288.png)
and when we have an exponent of an exponent, we can simplify by multiplying these two exponents.
3ร(x-3) = 3x - 9
and therefore we get
![{2}^{3x - 9}](/tpl/images/1398/5502/1e2d3.png)
and by the way, we can now even easily solve this for x, as we know
![{2}^{4x} = {2}^{3x + x}](/tpl/images/1398/5502/28079.png)
after all, because 4x = x + x + x + x = 3x + x = ...
and because we got also
![{2}^{4x} = {2}^{3x - 9}](/tpl/images/1398/5502/2e11d.png)
we know that 3x + x = 3x - 9
and that gives us x = -9