SOLUTION: Please help me multiply these two fractions together. y^2 -6y + 9 over 8 multiplied by 4y + 12 over y^2 -9.

Algebra ->  Exponents-negative-and-fractional -> SOLUTION: Please help me multiply these two fractions together. y^2 -6y + 9 over 8 multiplied by 4y + 12 over y^2 -9.      Log On


   



Question 179755: Please help me multiply these two fractions together.
y^2 -6y + 9 over 8 multiplied by 4y + 12 over y^2 -9.

Found 2 solutions by solver91311, stanbon:
Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!




Step 1, factor the two numerators and the polynomial denominator.

First, . -3 times -3 is 9 and -3 plus -3 is -6, so this factors to:

Second, factor a 4 out of the other numerator:

Third, recognize the difference of two squares in the right-hand denominator: .


Putting all back together:



Multiplying rational expressions containing polynomials is exactly the same as multiplying regular fractions, i.e. numerator times numerator divided by denominator times denominator, so:




Finally, eliminate factors common to both numerator and denominator:




John


Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
[(y^2 -6y + 9) /8] * [(4y + 12) / (y^2 -9)]
Factor where you can:
[(y-3)^2/8] * [4(y+3)/(y-3)(y+3)]
Cancel any factor that is common to a numerator and a denominator,
such as (y-3), 4, (y+3) :
[1/2] * [1/1]
= 1/2
========================
Cheers,
Stan H.