Exploring Quadratic Graphs
posted by Emily on .
ok, I totally did not get this question at all.
Complete each statement. Assume the variable a does not equal 0.
a. The graph of y=ax^2+c intersects the xaxis in two places when ______.
b. The graph of y=ax^2+c does not intersect the xaxis when ______.

Plz somebody explain this to me. Any help is greatly appreciated!!!
This equation is a parabola. In order for it to intersect the xaxis in 2 places, the bottom point of the parabola has to be below the xaxis. Therefore, the point c, which is the minimum of the parabola (where x is 0) has to be less than 0. If c is >0, then it does not cross the xaxis, because the whole graph sits above the xaxis.
oh, i get it now!!! Thanx so so much! You guys help me out a lot!

y=4x^2