SOLUTION: If f(2)=1 and f(4)=-2 then what is f(x)? I just don't know how to do it....

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Question 776566: If f(2)=1 and f(4)=-2 then what is f(x)?

I just don't know how to do it....
Answer by rothauserc(4718) About Me  (Show Source):
You can put this solution on YOUR website!
we are given two points and need to wrte the equation for the line
the two points are (2,1) and (4,-2)
the standard form for a line is y = mx +b
m = 1 - (-2) / 2 - 4 = -(3/2)
1 = -(3/2)*2 +b
1 = -3 + b
b = 4
the function is f(x) = -(3/2)x +4