Posted by Vanessa on Sunday, February 3, 2013 at 12:33pm.
The Brooklyn Bridge in New York City is a suspension bridge that crosses the East River and connects Brooklyn to the island of Manhattan. If the origin is placed at the top of one of the cable suport towers, as shown, the shape of a cable that supports the main span can be modelled by the equation
h=0.0008d^20.384d were h metres represents the height and d metres represents the horizontal distance.
a) What is the vertical distance from the top of a support tower to the lowest point on a cable, to the nearest metre?
b)What is the length of the main span?
c) At a horizontal distance of 50m from one end of the cable, how far is the cable below the top of the support towers, to the nearest metre?

Grade 10 Math  Steve, Sunday, February 3, 2013 at 2:21pm
h = .0008(d^2480d)
= .0008(d^2480d+240^2  240^2)
= .0008(d240)^2  46.08
So, the vertex is at (240,46.08)
That means the drop is 46 m
h = .0008d(d480)
h=0 at d=0,480
The main span is 480 m
h(50) = .0008*50(430) = 17.2
The point is 17 m below the top
Answer This Question
Related Questions
 8th grade  I need to find the percent of the total area of New York City that ...
 trig  The high level bridge, a railway bridge that crosses the Oldman River is ...
 Math, Trig  The high level bridge, a railway bridge that crosses the Oldman ...
 math  In a suspension bridge, the shape of the suspension cables is parabolic. ...
 math  The main span of a suspension bridge is the roadway between the bridge's ...
 Math stem question  The main span of a suspension bridge is the roadway between...
 physics  A suspension bridge supported by a cable 100ft long has a sag of 10ft ...
 englishmetaphor  All sentences must be properly constructed. Finally, you are...
 algebra  You live near a bridge that goes over a river. The underside of the ...
 Mathsoh cah toa  A bridge is 140m long.From the ends of the bridge, the angles...
More Related Questions