<PRE><B>Question 40475</B>
(y^2-81)/y^2 * (y^2-9y)/(y^2+y-90)

Factor where you can as follows:

[(y-9)(y+9)]/y^2 * y(y-9)/[(y+10)(y-9)]

Look for factors that are common to numerator and denominator: such
as y and (y-9); cancel them as follows:

[(y-9)(y+9)]/y* 1/[y+10]

Multiply the fractions to get:

[y^2-81]/[y(y+10)]
Cheers,
Stan H.

 
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