SOLUTION: Solve. Write the solution set using interval notation. x^2 + 3x > 40

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Question 1058964: Solve. Write the solution set using interval notation.
x^2 + 3x > 40
Found 2 solutions by josgarithmetic, ikleyn:
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
x%5E2%2B3x-40%3E0

The roots are the critical values.

If you recognize that the quadratic is a parabolic function then you may know enough that this has vertex minimum and opens upward, since lead coefficient is positive.

%28x-5%29%28x%2B8%29%3E0
Should be clear - solution not between the roots.

Answer by ikleyn(52781) About Me  (Show Source):
You can put this solution on YOUR website!
.
The solution is this set:

x < -8   OR   x > 5.

In the interval notation,  the solution set is  (-infinty,-8) U (5,infinity).