Question

can someone actually help me on a calculus problem?

Answer 1

do you understand , for example, a quadratic might *never* cross the x-axis (which of course means no x-intercepts). This happens for a U shaped curve above the x-axis.

Of course, the quadratic has 2 roots, but they will be imaginary.

Or, as pointed out in your other post, the quadratic might touch the x-axis only once (when the vertex of the quadratic is the only point that touches the x-axis)
in that case you have 1 x-intercept, and the "roots' are "repeated" (same root , twice)

Answer 2

and an example like @inkyvoyd said would be (x-1)^2=0