Question

How do you find the derivative of a graph?

Answer 1

Draw the slopes at various values of x for y=f(x)
Slope is change in y divided by change in x

The slopes are the derivatives of F(x) at these x values.

Do enough of these to be able o put a smooth curve through them
on your f'(x) vs. x new graph.

Answer 2

How do I know if it's a parabola opening upwards or downwards?

Answer 3

Parabola open upwards will have the slopes go from negative
to positive as x increases. (Second derivative is >0.)
Opposite for parabola open downwards.