MATH 1720
Name___________________________________
Quiz 12
Due: Thursday, April 16
Show all work to receive full credit.
Find the focus and directrix of the parabola.
1)
-
1
8x2 = y
1)
2)
x = 4y
2
2)
Find an equation of a parabola satisfying the given conditions.
3)
Focus at (
5
, 0), directrix x
=
-
5
3)
Solve the problem.
4)
A building has an entry with the shape of a parabolic arch
40
feet high and
48
feet wide at
the base. Find an equation for the parabola if the vertex is placed at the origin of the
coordinate system.
40 ft
48 ft
4)
Find the center and the radius of the circle.
5)
x
2
+ y
2
- 4x + 8y = -16
5)
1
