SOLUTION: For all a, (3a+4)(4a-3)=

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Question 196991: For all a, (3a+4)(4a-3)=
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!

%283a%2B4%29%284a-3%29 Start with the given expression.


Now let's FOIL the expression.


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


%28highlight%283a%29%2B4%29%28highlight%284a%29-3%29 Multiply the First terms:%283a%29%284a%29=12a%5E2.


%28highlight%283a%29%2B4%29%284a%2Bhighlight%28-3%29%29 Multiply the Outer terms:%283a%29%28-3%29=-9a.


%283a%2Bhighlight%284%29%29%28highlight%284a%29-3%29 Multiply the Inner terms:%284%29%284a%29=16a.


%283a%2Bhighlight%284%29%29%284a%2Bhighlight%28-3%29%29 Multiply the Last terms:%284%29%28-3%29=-12.


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So we have the terms: 12a%5E2, -9a, 16a, and -12


12a%5E2-9a%2B16a-12 Now add every term listed above to make a single expression.


12a%5E2%2B7a-12 Now combine like terms.


So %283a%2B4%29%284a-3%29 FOILs to 12a%5E2%2B7a-12.


In other words, %283a%2B4%29%284a-3%29=12a%5E2%2B7a-12.