SOLUTION: 81-25w^2

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Question 481878: 81-25w^2
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!

81-25w%5E2 Start with the given expression.


%289%29%5E2-25w%5E2 Rewrite 81 as %289%29%5E2.


%289%29%5E2-%285w%29%5E2 Rewrite 25w%5E2 as %285w%29%5E2.


Notice how we have a difference of squares A%5E2-B%5E2 where in this case A=9 and B=5w.


So let's use the difference of squares formula A%5E2-B%5E2=%28A%2BB%29%28A-B%29 to factor the expression:


A%5E2-B%5E2=%28A%2BB%29%28A-B%29 Start with the difference of squares formula.


%289%29%5E2-%285w%29%5E2=%289%2B5w%29%289-5w%29 Plug in A=9 and B=5w.


So this shows us that 81-25w%5E2 factors to %289%2B5w%29%289-5w%29.


In other words 81-25w%5E2=%289%2B5w%29%289-5w%29.