SOLUTION: Solve the polynomial inequality and graph the solution set on a number line. Express the solution set in interval notation.
5x^2-3x is greater than or equal to 8
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-> SOLUTION: Solve the polynomial inequality and graph the solution set on a number line. Express the solution set in interval notation.
5x^2-3x is greater than or equal to 8
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Question 156261: Solve the polynomial inequality and graph the solution set on a number line. Express the solution set in interval notation.
5x^2-3x is greater than or equal to 8 Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! Express the solution set in interval notation.
5x^2-3x is greater than or equal to 8
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5x^2 - 3x -8 >= 0
5x^2 -8x+5x -8 >= 0
x(5x-8) +(5x-8)
(5x-8)(x+1) >= 0
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Solve the EQUALITY:
x = 8/5 or x = -1
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Draw a number line: plot -1 and 8/5 on it.
Check a test point from each resulting numberline interval in the INEQUALITY.
Let x = -2; you get 5(-2)^2-3*-2-8 >0; true; solutions in (-inf,-1)
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Let x = 0; you get 5*0 - 3*0 -8 > 0 ; false; no solutions in (-inf,1)
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Let x = 2; you get 5(2)^2-3*2-8 >0 ; true; solutions in (8/5,+inf)
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Final Answer: {x| x<=-1} U {x|x >= 8/5}
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Cheers,
Stan H.
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