SOLUTION: if f(x) is aquadratic polynomial such that f(2)=-3 and f(-2)=21, then the coefficient of x in f(x) is A)4 B)7 C)-6 D)-3

Algebra ->  Proofs -> SOLUTION: if f(x) is aquadratic polynomial such that f(2)=-3 and f(-2)=21, then the coefficient of x in f(x) is A)4 B)7 C)-6 D)-3      Log On


   

Question 687864: if f(x) is aquadratic polynomial such that f(2)=-3 and f(-2)=21, then the coefficient of x in f(x) is
A)4
B)7
C)-6
D)-3
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
if f(x) is aquadratic polynomial such that f(2)=-3 and f(-2)=21, then the coefficient of x in f(x) is
A)4
B)7
C)-6
D)-3
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Form: ax^2 + bx + c = y
---
Using (-2,21)::: 4a -2b + c = 21
Using (2,-3):::: 4a +2b + c = -3
----
Subtract and solve for "b":
4b = -24
b = -6
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Cheers,
Stan H.
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