SOLUTION: x^2-2x-3>0 pls help e to solve this quadratic inequalities.

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Question 890393: x^2-2x-3>0
pls help e to solve this quadratic inequalities.
Answer by josgarithmetic(39618) About Me  (Show Source):
You can put this solution on YOUR website!
You still look for the roots but you now also decide which interval or intervals makes the inequality true.


x%5E2-2x-3=%28x%2B1%29%28x-3%29%3E0

The zeros or roots would be the critical points, making three intervals:
(-infinity, -1), (-1, 3), (-3, infinity).
Pick any value in each interval and test if satisfies the inequality.

You should find that the solutions are highlight%28x%3C-1%29 or highlight%28x%3E3%29.