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) (Show Source):
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:
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
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Cheers,
Stan H.