<PRE><B>Question 87026</B>
1. 9-x^2 = (3-x)(3+x)
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2.4x^2+81-36x = 4x^2-36x+81 = (2x-9)(2x-9) 
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3.4y^2+16y+16 = (2y+4)(2y+4)
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4.x^2-25 = (x-5)(x+5)
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Cheers,
Stan H.
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