Question

The dome over the town hall has a parabolic shape. I measure 48 m across and rises 12 m at its center. Determine the quadratic equation that models the shape of the parabola.

I have learned the formula y = a(x-s)(x-t).

Answer 1

so one side is at zero, and at 48m, it comes to zero again.
y=a(x)(x-48)
and at x=24 (half way across), y=12
12=a(24)(-24)
solve for a ( I get in my head -1/48)