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put this solution on YOUR website!the maximum of the graph lies on the axis of symmetry (at the vertex of the parabola)
the general equation for the axis of symmetry is x=-b/(2a)
in this case, t=-200/(2(-5)) __ t=-200/-10 __ t=20
substituting __ h=-5(20^2)+200(20) __ h=-2000+4000 __ h=2000