SOLUTION: Write an equation for a function with a graph that has x-intercepts at –3, 4 and 6

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Question 890231: Write an equation for a function with a graph that has x-intercepts at –3, 4
and 6
Answer by nerdybill(7384) About Me  (Show Source):
You can put this solution on YOUR website!
Write an equation for a function with a graph that has x-intercepts at –3, 4
and 6
.
From each intercept, we can derive a "factor":
(x+3)(x-4)(x-6)
we multiply the above together to get the polynomial
(x^2-x-12)(x-6)
x(x^2-x-12) - 6(x^2-x-12)
(x^3-x^2-12x) - (6x^2-6x-72)
x^3-x^2-12x - 6x^2+6x+72
x^3-7x^2-12x+6x+72
x^3-7x^2-6x+72 (this is what they're looking for)