SOLUTION: (x + 9) (x - 4)

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Question 148775: (x + 9) (x - 4)
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!

%28x%2B9%29%28x-4%29 Start with the given expression


Now let's FOIL the expression



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


%28highlight%28x%29%2B9%29%28highlight%28x%29-4%29 Multiply the First terms:%28x%29%2A%28x%29=x%5E2


%28highlight%28x%29%2B9%29%28x%2Bhighlight%28-4%29%29 Multiply the Outer terms:%28x%29%2A%28-4%29=-4x


%28x%2Bhighlight%289%29%29%28highlight%28x%29-4%29 Multiply the Inner terms:%289%29%2A%28x%29=9x


%28x%2Bhighlight%289%29%29%28x%2Bhighlight%28-4%29%29 Multiply the Last terms:%289%29%2A%28-4%29=-36


x%5E2-4x%2B9x-36 Now collect every term to make a single expression



x%5E2%2B5x-36 Now combine like terms


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Answer:
So %28x%2B9%29%28x-4%29 foils and simplifies to x%5E2%2B5x-36

In other words, %28x%2B9%29%28x-4%29=x%5E2%2B5x-36