a suspension bridge has twin towers that extend429 ft above the road surface and are 3870 ft apart. The cab;es are parabolic in shape and are suspended from the tops of the towers. the cables just touch the road surface at the center of the bridge find the height of the cables at a point on the road surface 646 ft from the center.
HELP
- Thread starter frichar3
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- Feb 4, 2004
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Let the center of the roadbed for this bridge be at the origin, (0, 0). Then the bridge extended (1/2)(3870) = 1935 feet on either side of this point.
Then the parabola has its vertex at (h, k) = (0, 0), with a point at (1935, 429). Use this information, along with the vertex form of the equation, "y = a(x - h)<sup>2</sup> + k", to find the parabola equation for this bridge.
Then evaluate y at x = 646.
If you get stuck, please reply showing how far you have gotten. Thank you.
Eliz.
Then the parabola has its vertex at (h, k) = (0, 0), with a point at (1935, 429). Use this information, along with the vertex form of the equation, "y = a(x - h)<sup>2</sup> + k", to find the parabola equation for this bridge.
Then evaluate y at x = 646.
If you get stuck, please reply showing how far you have gotten. Thank you.
Eliz.