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A linear function has f(1) = -1 and f(4) = 5. find its equation f(x)

User Renny
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1 Answer

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Answer: y = 2x - 3
Step-by-step explanation:
Using rise over run, 5 - - 1 / (4 - 1) = 6/3= 2.
Plugging that slope into the slope intercept formula, y =2x + b.
The constant b can be found by plugging in a point and solving for b.
Plugging in the point (1,-1), -1 = 2(-1) + b,
so b = -3 and the function is y = 2x - 3.
User Florian Lavorel
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