SOLUTION: Solve each inequality by using the graphical method. State the solution set in interval notation. {{{x^2-2x-3>0}}}

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Question 1030189: Solve each inequality by using the graphical method. State the solution set in interval notation.
x%5E2-2x-3%3E0
Answer by Edwin McCravy(20060) About Me  (Show Source):
You can put this solution on YOUR website!
We draw the graph of y=x%5E2-2x-3 by plotting points:

(-2,5), (-1,0), (0,-3), (1,-4), (2,-3), (3,0), (4,5)

 

Since we want to solve x%5E2-2x-3%3E0, and we have the 
graph of y=x%5E2-2x-3, so we want to know where y is
greater than 0.  So the solution will be the values of x
fro which the graph is ABOVE the x-axis.  Not including
the intercepts, the red part of the graph is ABOVE the 
x-axis and the green part is below the x-axis. So the part
of the x-axis that the red part of the graph is above,
is given interval notation as 

Edwin