SOLUTION: how do i find the discriminant of -x squared minus x = 4

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Question 210191: how do i find the discriminant of -x squared minus x = 4
Found 2 solutions by jim_thompson5910, stanbon:
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
-x%5E2-x=4 Start with the given equation.


-x%5E2-x-4=0 Subtract 4 from both sides.


From -x%5E2-x-4 we can see that a=-1, b=-1, and c=-4


D=b%5E2-4ac Start with the discriminant formula.


D=%28-1%29%5E2-4%28-1%29%28-4%29 Plug in a=-1, b=-1, and c=-4


D=1-4%28-1%29%28-4%29 Square -1 to get 1


D=1-16 Multiply 4%28-1%29%28-4%29 to get %28-4%29%28-4%29=16


D=-15 Subtract 16 from 1 to get -15


So the discriminant is -15.

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
find the discriminant of -x squared minus x = 4
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Rearrange:
-x^2 - x - 4 = 0
x^2 + x + 4 = 0
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discriminant = b^2 -4ac = 1^2 - 4*1*4 = 1-16 = -15
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Cheers,
Stan H.