SOLUTION: Suppose f(x) is a linear function such that f(-1/2)=-7 and f(1)=-3. What is f(-3)?

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Question 1017089: Suppose f(x) is a linear function such that f(-1/2)=-7 and f(1)=-3. What is f(-3)?
Answer by amarjeeth123(570) About Me  (Show Source):
You can put this solution on YOUR website!
Let the linear function be a+bx
We have a-(b/2)=-7............equation 1
a+b=-3........................equation 2
Subtracting equation 1 from equation 2 we get,
b+(b/2)=4
3b/2=4
b=8/3
From equation 2 we get,
a=-3-8/3=-17/3
The linear function is (-17/3)+(8/3)x.
Verification steps:
a+b=-17/3+8/3=-9/3=-3
a-(b/2)=-17/3+(8/3)(-1/2)=-21/3=-7