Problems
Problem :
Is the major axis of the following ellipse horizontal or vertical:
+
= 1
?
a > b
, and
6 > 4
. Therefore,
a
2
is the denominator of the
x
2
term, so
the axis is horizontal.
Problem :
Find
a
,
b
, and
c
of the ellipse
+
= 1
.
a = 5
,
b = 4
, and
c =
= 3
.
Problem :
Find
a
,
b
, and
c
of the ellipse
9x
2 +3y
2 - 36x - 6y + 12 = 0
.
By completing the square and factoring, you arrive at the standard equation
for an ellipse.
a = 3
,
b =
, and
c =
.
Problem :
Find the vertices of the ellipse
2x
2 +3y
2 - 6 = 0
.
a =
, the major axis is horizontal, and the center of the ellipse
is
(0, 0)
. The vertices are at
(
, 0)
and
(-
, 0)
.
Problem :
What is the eccentricity of the ellipse
81x
2 + y
2 - 324x - 6y + 252 = 0
?
After completing the square and converting the equation to standard form, you
find
a = 9
,
b = 1
, and
c =
. Therefore,
e =
=
.
Problem :
What is the center and radius of the circle
x
2 + y
2 - 8x - 16y + 60 = 0
?
Center:
(4, 8)
; Radius =
= 2
.