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vivalakoda
How to find the discriminant of a parabola?
Y=-0.2x^2+1.62x+4 is the quadratic equation, I'm trying to find the discriminant but I'm stuck on how.
take what ever is under the root sign from the quadratic formula: \[Dis =b^2-4ab\] this will give you clues as to how many roots the parabola has
the equation you have listed: \[y= -0.2x^2+1.62x+4\] is not the quadratic equation, but rather the standard form of a quadratic function
match your equation to the standard from \[ a x^2 +b x+c =0 \] in your case a= -0.2, b=1.62 and c=4 now use the formula (see Mathmuse post) See http://www.mathwarehouse.com/quadratic/discriminant-in-quadratic-equation.php