Pre-Calc/Chapter 8: Analytic Geometry in Two- and Three-Dimensions/8.1 Conic Sections and Parabolas/8.1.6 Solve Apps: Parabolas
Parabolic Focus
A radio telescope has a parabolic surface. If it is #a m deep and 12 m wide, how far is the focus from the vertex? (round to tenths)]]>
1.0000000
0.3333333
0
0
#answer]]>
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Solve the problem. 20 m 1 mA radio telescope has a parabolic surface. If it ...
Solve the problem.
20 m
1 m
A radio telescope has a parabolic surface. If it is 1 m deep and 20 m wide, how far is the focus from the vertex?]]>
1.0000000
0.3333333
0
true
true
abc
5 m
Incorrect
100 m
Incorrect
1 m
Incorrect
25 m
Correct
Solve the problem. 39 m 10 mA tunnel is in the shape of a parabola. The ...
Solve the problem.
39 m
10 m
A tunnel is in the shape of a parabola. The maximum height is 39 m and it is 10 m wide at the base. What is the vertical clearance 4 m from the edge of the tunnel?]]>
1.0000000
0.3333333
0
true
true
abc
1.6 m
Incorrect
37.4 m
Correct
2.3 m
Incorrect
36.7 m
Incorrect
Solve the problem. 58 ft 28 ftA building has an entry the shape of a ...
Solve the problem.
58 ft
28 ft
A building has an entry the shape of a parabolic arch 58 ft high and 28 ft wide at the base. Find an equation for the parabola if the vertex is put at the origin of the coordinate system.]]>
1.0000000
0.3333333
0
true
true
abc
2 = -13.5x]]>
Incorrect
2 = -3.4y]]>
Correct
2 = -3.4x]]>
Incorrect
2 = -13.5y]]>
Incorrect
Solve the problem.A domed ceiling is a parabolic surface. For the best ...
Solve the problem.
A domed ceiling is a parabolic surface. For the best lighting on the floor, a light source is to be placed at the focus of the surface. If 3 m down from the top of the dome the ceiling is 18 m wide, find the best location for the light source.]]>
1.0000000
0.3333333
0
true
true
abc
6.8 m down from the top
Correct
20.4 m down from the top
Incorrect
13.6 m down from the top
Incorrect
27 m down from the top
Incorrect