SOLUTION: f is a linear function. 1.) If f(2) = 10 and f(10) = -2, find f(-10) and f(100) I really have no idea what to do.Help? Thank You!

Algebra ->  College  -> Linear Algebra -> SOLUTION: f is a linear function. 1.) If f(2) = 10 and f(10) = -2, find f(-10) and f(100) I really have no idea what to do.Help? Thank You!      Log On


   

Question 267616: f is a linear function.
1.)
If f(2) = 10 and f(10) = -2, find f(-10) and f(100)
I really have no idea what to do.Help?
Thank You!
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
f is a linear function.
If f(2) = 10
f(10) = -2
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slope = (10--2)/(2-10) = 12/-8 = -3/2
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Form: y = mx + b
You know m = -3/2 and y = 10 when x = 2.
Solve for "b":
10 = (-3/2)2 + b
b = 13
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Equation:
f(x) = (-3/2)x + 13
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find f(-10) = (-3/2)(-10) + 13 = 28
and f(100) = (-3/2)(100) + 13 = -150 + 13 = -137
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Cheers,
Stan H.
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