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4. The equation of the major axis is y = 0 and the equation of the minor axis is x`= 0 if

a > b.

5. The x-axis and y-axis are axes of symmetry.

6. This ellipse intersects the x-axis at points A(−a,0) and B(a,0) and intersects the y-

axis at points

points C(0,−b) and D(0,b). The four points are called the vertices of the ellipse.

7. AB = 2a is called the long axis and CD = 2b is called the short axis.

ACTIVITY 3

1. The equation of the ellipse is 9 + 25 = 225
2
2
Determine the vertices of the ellipse, and the focal points, then sketch the ellipse!

Answer :

2
2
9 + 25 = 225

. . . . 2 … 2
 + = 1
… . . … . .

2 2
 + = 1
25 9

So that it is obtained

2
a = … →a = ±5

2
b = … → b = ± 3

So the vertices of the ellipse are A (…, ...),

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