Do you mean an extraneous solution? I will tell you what I think. To tell if a solution is extraneous you need to go back to the original problem and check if there actually is a solution or if the solution is actually right. If not then it is extraneous.
Let n be a number of friends at the perty. If <span>dinner costs $30 per person, then it cost $30n for all friends.
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Robert has booked a banquet hall which costs <span>$200, then his total expenses are $200+30n.
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If the final bill is p, then p=<span>200+30n.
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Answer: p=<span>200+30n.</span>
Here given, 
and 
we have to find 
which means the subtracting of the functions f(x) and g(x).
= 
= 
= 
( we know that multiplication of negative and negative is positive)
= 
=
We have got the required answer here.
Please provide more context for our brains to understand your problem (: thank you!
