SOLUTION: okay i had a math problem in class today and this isn't from a textbook here it is Input----Output 1------ 4 2------ 8 3------ 24 4------ X Solve X, and the answer

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Question 205527: okay i had a math problem in class today and this isn't from a textbook
here it is
Input----Output
1------ 4
2------ 8
3------ 24
4------ X
Solve X, and the answer is not 4, 96, or 32. Please Help me ASAP!!!!!

Found 2 solutions by Targetweek, Edwin McCravy:
Answer by Targetweek(62) About Me  (Show Source):
You can put this solution on YOUR website!
i used a regression calculator on another website
sorry i can't explain how to do it
the equation is gave me is y+=+6+x%5E2++-14x+%2B+12
and when x = 4 then y = 52

Answer by Edwin McCravy(20056) About Me  (Show Source):
You can put this solution on YOUR website!
okay i had a math problem in class today and this isn't from a textbook
here it is
Input----Output
1------ 4
2------ 8
3------ 24
4------ X
Solve X, and the answer is not 4, 96, or 32. Please Help me ASAP!!!!!

Use a quadratic polynomial in n:

When the Input is n, assume the Output is An%5E2+%2B+Bn+%2B+C.

Substituting the given data:

When the Input is 1, the Output is A%281%29%5E2+%2B+B%281%29+%2B+C=A%2BB%2BC=4.
When the Input is 2, the Output is A%282%29%5E2+%2B+B%282%29+%2B+C=4A%2B2B%2BC=8.
When the Input is 3, the Output is A%283%29%5E2+%2B+B%283%29+%2B+C=9A%2B3B%2BC=24.

So we solve the system of equations:

system%28A%2BB%2BC=4%2C4A%2B2B%2BC=8%2C9A%2B3B%2BC=24%29

Solve that system by any method you know, and get

A=6, B=-14, and C=12

So the expression

An%5E2+%2B+Bn+%2B+C

becomes

6n%5E2+-+14n+%2B+12. Therefore, to check the first three terms in
the equation to see if it is correct:

When the Input is 1, the Output is 6%281%29%5E2+-+14%281%29+%2B+12=6-14%2B12=4.
When the Input is 2, the Output is 6%282%29%5E2+-+14%282%29+%2B+12=24-28%2B12=8.
When the Input is 3, the Output is 6%283%29%5E2+-+14%283%29+%2B+12=54-42%2B12=24.

Those are correct, so to get the next term we substitute n=4:

When the Input is 4, the Output is 6%284%29%5E2+-+14%284%29+%2B+12=96-56%2B12=52.

Edwin