How would you solve a problem like this: (x+8)(x-16)(x+2)>0

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Hi Lovbears, There are several ways to solve this problem.  Your answer will be alternating intervals on a number line.  The method I like is to find the point at which each factor = 0... in other words, when x + 8 = 0, when x - 16 = 0, and when x + 2 = 0.  the values are -8. 16, and -2... like Steve said!  Mark these point on your number line to create 4 zones.  Pick a point between each of the 2 endpoints of each section as a "test point"... this value will tell you whether that interval is part of the solution or not.  For example, between -8 and -2, a test point could be -5.  When I substitute that value for x in each factor of the inequality, I get (3)(-21)(-3)>0.  Without doing the multiplication, you know that the product of 2 negatives is a positive, so -5 will make the inequality > 0.  The interval, (-8, -2) IS part of the solution.  Next, you can test each of the other 3 sections of the graph to see if they make the inequality true or false.  A shorter way, is by using the alternating signs rule.  Every other section of the graph will make the inequality true so you only have to test one value.  Hope this helps!  (Kind of wordy!)