The height h above the roadway of the main cable of the Golden Gate Bridge can be modeled by the function h(x) = 1/9000x^2-7/15x+500, where x is the distance in feet from the left tower.
a. Complete the square, and write the function in vertex form.
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b. What is the vertex, and what does it represent?
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c. The left and right towers have the same height. What is the distance between them?
Disdance: d=4200 feet.