SOLUTION: i need your help 2x^2 -3x -2<=0 ? my answer is -0.5 <= x <= 2 but the answer key is 0.5 <= x <= 2 My answer or the answer key is wrong ? thx

Question 961658: i need your help 2x^2 -3x -2<=0 ?
my answer is -0.5 <= x <= 2
but the answer key is 0.5 <= x <= 2
My answer or the answer key is wrong ?
thx
Answer by Theo(13342) (Show Source): You can put this solution on YOUR website!
equation is:
2x^2 - 3x - 2 <= 0
set it equal to 0 and you get:
2x^2 - 3x - 2 = 0
factor it and you get:
x = -.5 and or x = 2
graph it on the number line and you see that the function is greater than 0 when x is smaller than -.5 and it is less then 0 when x is between -.5 and 2 and it is greater than 0 when x is greater than 2.
bottom line:
you are correct and the book is wrong.
it happens more times than you think.
the books are not perfect.
here's a graph of your equation.

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