Module 6: Lesson 5
 
Are You Ready?

    1. This inequality can be solved graphically. Graph the function y = x2 − 2x − 8 and see where the function is greater than zero.

       
      This is a graph of the function y equals x squared minus 2x minus 8. The x-intercepts are shown to be at (negative 2, 0) and (4, 0).

      From the graph, the function y = x2 − 2x − 8 is greater than zero when x < −2 or x > 4.

      So, for the inequality x2 − 2x − 8 > 0, x < −2 or x > 4.


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