How to get Formula from a Cubic Graph

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Jordash
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Homework Statement



The figure shows the graph of a cubic polynomial.

GraphFigure.png
The function graphed is f(x)=

Hint: You may write the function as f(x) = a(x-b)(x-c)(x-d) where b, c, and d, are integers and a is a fraction.

Homework Equations


The Attempt at a Solution



I'm lost...
 
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When f(x)=0 the graph cuts the x-axis, so what are the values of b,c and d?
 
b, c and d are where f(x)=0, can't you read those off from the graph? Now what about a?
 
I'm sorry but both of those answers made no sense...
 
Jordash said:
I'm sorry but both of those answers made no sense...

Are you unable to read the number off of the graph? Which part made no sense?
 
Simply by observing the graph you should be able to find b, c, and d in your equation f(x) = a(x -b)(x - c)(x - d).

And you should be able to get a by noticing where the graph crosses the y-axis.