SOLUTION: can you solve this inequality? x^2-2x-5 is greater than or equal to 3? I worked the problem and got x is greater than or equal to 10. is this correct?

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Question 1044150: can you solve this inequality?
x^2-2x-5 is greater than or equal to 3?
I worked the problem and got x is greater than or equal to 10. is this correct?
Answer by ikleyn(52767) About Me  (Show Source):
You can put this solution on YOUR website!
.can you solve this inequality?
x^2-2x-5 is greater than or equal to 3?
I worked the problem and got x is greater than or equal to 10. is this correct?
~~~~~~~~~~~~~~~~ 

x%5E2-2x-5 >= 3   is equivalent to

x%5E2-2x-8 >= 0.

Factor the left side:

%28x-4%29%2A%28x%2B2%29 >= 0.

The solution is  -infinity < x <= -2  and  4 <= x < infinity.

See the plot below.


graph%28+330%2C+330%2C+-10.5%2C+10.5%2C+-10.5%2C+10.5%2C%0D%0A++++++++++x%5E2-2x-8%0D%0A%29

Figure. Plot f(x) = x%5E2-2x-8