SOLUTION: find the discriminant. how many real solutions does the equation have? -4x^2-4=8x

Algebra ->  Quadratic Equations and Parabolas -> SOLUTION: find the discriminant. how many real solutions does the equation have? -4x^2-4=8x      Log On


   

Question 1071181: find the discriminant. how many real solutions does the equation have? -4x^2-4=8x
Found 2 solutions by josgarithmetic, MathTherapy:
Answer by josgarithmetic(39620) About Me  (Show Source):
You can put this solution on YOUR website!
Discriminant?


-4x%5E2-4=8x
-4x%5E2-8x-4=0
x%5E2%2B2x%2B1=0


Now discriminant? But here, not really needed because you know that quadratic expression is factorable. ONE REAL SOLUTION. Why? You know the quadratic there is a perfect square.
x%5E2%2B2x%2B1=0
%28x%2B1%29%28x%2B1%29=0
%28x%2B1%29%5E2=0


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Discriminant here is 2%5E2-4%2A1%2A1=4-4=highlight%280%29.
That is what you get when the quadratic expression is a perfect square trinomial.

Answer by MathTherapy(10552) About Me  (Show Source):
You can put this solution on YOUR website!

find the discriminant. how many real solutions does the equation have? -4x^2-4=8x


Discriminant: {{b^2 - 4ac}}}

a = - 1   ;   b= - 2     ;   c = - 1



As discriminant = 0, there will be: .