Question 256170
can you help me solve {{{5^(n-1) = 1/25}}}
<pre>
{{{5^(n-1)= 1/25}}}

Since the base of the exponent on the left is 5,
we try to write the 25 also as a power of 5. So
write 25 as {{{5^2}}}

{{{5^(n-1)= 1/(5^2)}}}

Now write the whole right side as a power of 5
by writing it as {{{5^(-2)}}}

{{{5^(n-1)= 5^(-2)}}}

Now we use the principle that if two exponentials
are equal which have the same base, and the common base
is positive and not 1, then the exponents are
equal:

{{{n-1=-2}}}

{{{n=-1}}}

Edwin</pre>