9514 1404 393
Answer:
x = 3
Explanation:
The equation can be rewritten to make use of the graphing calculator's ability to identify function zeros:
x(x -2)(x +3) -18 = 0
The attached shows x = 3 is the only real solution.
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We're not sure what "system of equations" is intended. Perhaps it is ...
y = 18
y = x(x -2)(x +3)
To create the expression we graphed, we effectively subtracted the first equation from the second.