Question 806652
<pre>
  x² - 3x - 18 < 0
(x - 6)(x + 3) < 0

The critical numbers are 6 and -3

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-5 -4 -3 -2 -1  0  1  2  3  4  5  6  7  8

test value -4:  (-4)² - 3(-4) - 18 < 0
                      16 + 12 - 18 < 0
                                10 < 0
False do not shade (-infinity,-3)


test value 0:  (0)² - 3(0) - 18 < 0
                     0 + 0 - 18 < 0
                            -18 < 0
True, so shade (-3,6)

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-5 -4 -3 -2 -1  0  1  2  3  4  5  6  7  8


test value 7:  (7)² - 3(7) - 18 < 0
                    49 -21 - 18 < 0
                             10 < 0
False do not shade (6, infinity)

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-5 -4 -3 -2 -1  0  1  2  3  4  5  6  7  8

Answer (-3,6)

Edwin</pre>