Question 415237
Just write this expression without exponents:
{{{y*(y*y*y*y*y*y*y*y)*(y*y*y*y*y)}}}
Now what is this whole thing using exponents?
{{{y*(y*y*y*y*y*y*y*y)*(y*y*y*y*y) = y^14}}}
What did you do?
(1 y) x (8 y's) x (5 y's) = 14 y's 
( 1 + 8 + 5 = 14 )
So, to get the product of y's with exponents,
you just add the exponents
{{{y^1*y^8*y^5 = y^(1 + 8 + 5)}}}
Give yourself some more examples and practice
to drill it in.