The mean of 4 numbers is 15. 3 of the numbers are 18, 14 and 12. What is the other number?
1 answer:
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Answer:
3x^2 is the final solution
See the image below for step by step explanation.
Answer:
B. - 4x - 5
Step-by-step explanation:
(p о n) (x) is the same thing as (p(n(x))
We know n(x) = x - 5, so let's input that into our expression
(p(x - 5))
Since we know p(x) = x^2 + 6x, let's replace the x with the new value x-5. Now our expression is:
p(x) = (x - 5)^2 + 6(x - 5)
Now all we have to do is simplify.
(x - 5)^2 is the same as: (x - 5)(x - 5)
Using the foil method, it simplifies to: x^2 - 10x + 25
6 (x - 5) = 6x - 30
Now our expression is: x^2 - 10x + 25 + 6x - 30
Combine like terms: x^2 - 4x - 5
The expression is: - 4x - 5