Question

A rectangle is inscribed with its base on the x-axis and its upper corners ont the parabola y=5-x^2

Answer 1

\[y=5-x^2,x^2=-y+5=-\left( y-5 \right)\]
this is a downward parabola with vertex at (0,5)
cutting y-axis at (0,5) and x-axis at \[\left( -\sqrt{5},0 \right) ~and~\left( \sqrt{5},0 \right)\]

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