SOLUTION: I need help please. Please solve polynomial inequality and express solution set in interval notation x^2-3x-28<0 Thank You Holly

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Question 1049762: I need help please. Please solve polynomial inequality and express solution set in interval notation x^2-3x-28<0
Thank You
Holly
Found 2 solutions by ikleyn, Alan3354:
Answer by ikleyn(52775) About Me  (Show Source):
You can put this solution on YOUR website!
.
Factor the left side:


x%5E2-3x-28 = (x-7)*(x+4).


Now you have the same inequality in the form


(x-7)*(x+4) < 0.


Can you solve it on your own?


Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
I need help please. Please solve polynomial inequality and express solution set in interval notation x^2-3x-28<0
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Step 1, solve the equation.
x^2-3x-28 = 0
(x-7)*(x+4) = 0
x = -4, x = 7
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It's a parabola that opens upward.
The zeroes are -4 and 7.
It's below the x-axis between the zeroes --> < 0 between -4 and 7.
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-4 < x < 7 is the solution.