SOLUTION: please "multiply and simplify" (5x-3)(5x+3) thanks

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Question 194030: please "multiply and simplify"

(5x-3)(5x+3)

thanks
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!

%285x-3%29%285x%2B3%29 Start with the given expression.


Now let's FOIL the expression.


Remember, when you FOIL an expression, you follow this procedure:


%28highlight%285x%29-3%29%28highlight%285x%29%2B3%29 Multiply the First terms:%285%2Ax%29%2A%285%2Ax%29=25%2Ax%5E2.


%28highlight%285x%29-3%29%285x%2Bhighlight%283%29%29 Multiply the Outer terms:%285%2Ax%29%2A%283%29=15%2Ax.


%285x%2Bhighlight%28-3%29%29%28highlight%285x%29%2B3%29 Multiply the Inner terms:%28-3%29%2A%285%2Ax%29=-15%2Ax.


%285x%2Bhighlight%28-3%29%29%285x%2Bhighlight%283%29%29 Multiply the Last terms:%28-3%29%2A%283%29=-9.


25%2Ax%5E2%2B15%2Ax-15%2Ax-9 Now collect every term to make a single expression.


25%2Ax%5E2-9 Now combine like terms.


So %285x-3%29%285x%2B3%29 FOILs to 25%2Ax%5E2-9.


In other words, %285x-3%29%285x%2B3%29=25%2Ax%5E2-9.



Note: an alternative to FOILing is to use difference of squares formula