Question 411666
You have to remind yourself what exponents are.
Try a simple problem first. I always use this method of attack
{{{b^5/b^2 = (b*b*b*b*b) / (b*b) = b*b*b}}}
This tells me that {{{b^5/b^2 = b^3}}}, so just subtract the
bottom exponent from the top (or get a tired hand writing out 19 b's on
top and 12 b's on the bottom)
your problem:
{{{b^19/b^12 = b^7}}}
---------------------
What if the bigger number was on the bottom?
{{{b^12/b^19 = 1/b^7}}}
The result of the subtraction just ends up on the bottom
Hope this helps