I need to find the equation of a parabola in standard form if the domain of an arch under a bridge is {-50 <= x <= 50} and the range is {0<=y<=20}(adsbygoogle = window.adsbygoogle || []).push({});

The span of the arch is 100 metres and the height is 20 metres.

standard form of a parabola is

[tex] (x-h)^2=4p(y-k) [/tex]

i know the vertex is (0,20) so the equation should look like [tex] x^2=4p (y-20) [/tex] so far but im not sure what the focus is or how to determine it plz help me out

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# Homework Help: Loci Conics Parabola eqn in standard form

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