I'm stumped on these Parabola problems completely

[Milow]

Thanks for the post , what about the other questions?

The Lion's Gate Bridge in Vancouver , the Golden Gate Bridge in San Francisco , and the Brooklyn Bridge in New York City are examples of suspension bridges. A suspension bridge has 2 suspension cables that connect the tops of two towers. The roadway is suspended from these cables hence the name suspension bridge.

The height of a suspension cable above the roadway of a new suspension bridge , with two equally tall towers , is described by the equation y = 0.05(x-30)^2 + 6. In this equation , x represents the horizontal distance , in metres from one tower to the other tower , and y represents the height , in metres , of the cable above the roadway.

a) Complete the following table of values for the relationship

--------------------------------------…
Distance from First Tower , x (m) | Height of cable above roadway , y (m)

0 ,
6 ,
12,
18,
24,
30,
36,
42,
48,
--------------------------------------…

b) How high above the roadway is the suspension cable attached to the first tower?

c) Identify the coordinates of the vertex , the equation of the axis of axis of symmetry and the minimum value of the parabola.

e) How close to the roadway does the suspension cable dip? Justify your answer

f ) How far apart are the two towers? Explain how you deduced your answer

g) Vertical cables are used to join the suspension cable to the roadway. How long is the vertical cable that joins the suspension cable to the roadway at a point that is 6 m away from the first tower?

h) If vertical cables are required every 6m along the roadway , how much cable is needed for the entire bridge?

 

[wjm11]

The height of a suspension cable above the roadway of a new suspension bridge , with two equally tall towers , is described by the equation y = 0.05(x-30)^2 + 6. In this equation , x represents the horizontal distance , in metres from one tower to the other tower , and y represents the height , in metres , of the cable above the roadway.

a) Complete the following table of values for the relationship

--------------------------------------…
Distance from First Tower , x (m) | Height of cable above roadway , y (m)

0 ,
6 ,
12,
18,
24,
30,
36,
42,
48,
--------------------------------------…

b) How high above the roadway is the suspension cable attached to the first tower?

c) Identify the coordinates of the vertex , the equation of the axis of axis of symmetry and the minimum value of the parabola.

e) How close to the roadway does the suspension cable dip? Justify your answer

f ) How far apart are the two towers? Explain how you deduced your answer

g) Vertical cables are used to join the suspension cable to the roadway. How long is the vertical cable that joins the suspension cable to the roadway at a point that is 6 m away from the first tower?

h) If vertical cables are required every 6m along the roadway , how much cable is needed for the entire bridge?

Don't make it harder than it is. The numbers they gave you are just the x values. Plug them into the equation and find the corresponding y values. Plot these (x,y) points on a graph and you'll see the shape of the suspension bridge cable.

 

[Milow]

I did A , what about the others?

--------------------------------------…
Distance from First Tower , x (m) | Height of cable above roadway , y (m)

0 , 51
6 , 34.8
12, 22.2
18, 13.2
24, 7.8
30, 6
36, 7.8
42, 13.2
48, 22.2
--------------------------------------…

Alright what do I do for the other questions?

 

[wjm11]

Alright what do I do for the other questions?

Add a couple more points to your table -- up to x = 60. Then graph it and study the graph. It should become obvious.