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 Question from Icyy: how high is the parabolic arch of span 20 feet and height of 16 feet, at a distance 5 feet from the center? what equation will I be going to use? thank you

Hi,

Since it is a parabolic arch it is parabola opening downwards. I am going to place the base on the X-axis and have it symmetric around the Y-axis. It will intersect the Y-axis at $y = 16$ and since the span is 20 feet it will intersect the X-axis at $x = -10, x = 10.$ Hence its graph looks like

Parabolic Arch

Can you write its equation from this information?

Penny

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