Question 32296
I'm not too sure if this is what you want, but...
The difference of two squares.
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a² - b² = (a+b)(a-b)
Applying that to the polynomial (actually it's a binomial!)
49y² - 64 = (7y)² - (8)²
(7y)² - (8)² = (7y-8)(7y+8)
49y² - 64 = (7y-8)(7y+8)
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If this helps, good. If not, then can you just post your question again?