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The Hale Telescope The focus of the Hale telescope, in the accompanying figure, on Palomar Mountain in California is 55 ft above the mirror (at the vertex). The Pyrex glass mirror is 200 in. in diameter and 23 in. thick at the center. Find the equation for the parabola that was used to shape the glass. How thick is the glass on the outside edge?
HINT Find the equation of the parabola with focus (0, 55) that passes through the origin.
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