Question

This parabola can be modeled by the quadratic function y = 0.00012x2 + 6, where x represents the distance form the axis of symmetry and y represents the height of the cables.  The related quadratic equation is 0.00012x2 +6 = 0.
Calculate the value of the discriminant.

a.
-0.00056
c.
-0.00126
b.
-0.00288
d.
-0.00078

Answer 1

The discriminant,

$\Delta=b^2-4ac$

From, 

$ax^2+bx+c=0$

So,

$\Delta=-4(0.00012)6=-0.00288$