SOLUTION: Please help with the following? Factor completely 16r^2-9

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Question 376660: Please help with the following?
Factor completely
16r^2-9
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!

16r%5E2-9 Start with the given expression.


%284r%29%5E2-9 Rewrite 16r%5E2 as %284r%29%5E2.


%284r%29%5E2-%283%29%5E2 Rewrite 9 as %283%29%5E2.


Notice how we have a difference of squares A%5E2-B%5E2 where in this case A=4r and B=3.


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.


%284r%29%5E2-%283%29%5E2=%284r%2B3%29%284r-3%29 Plug in A=4r and B=3.


So this shows us that 16r%5E2-9 factors to %284r%2B3%29%284r-3%29.


In other words 16r%5E2-9=%284r%2B3%29%284r-3%29.


If you need more help, email me at jim_thompson5910@hotmail.com

Also, feel free to check out my tutoring website

Jim