Which of the following functions best describes this graph?
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Explanation:
The x intercepts or roots are x = 3 and x = 5, which lead to the factors x-3 and x-5 respectively.
Multiplying out those factors gets us this:
(x-3)(x-5)
x(x-5)-3(x-5)
x^2-5x-3x+15
x^2-8x+15