Write an equation for the following: a) The ellipse has foci (2, 0) and (–2, 0) and vertices (4, 0) and (–4, 0). b) The ellipse is centered at the origin, has axes of lengths 8 and 4, its major axis is horizontal.

Respuesta :

Answer:

a) [tex]\frac{x^2}{16} +\frac{ y^2}{12} = 1[/tex]

b) [tex]\frac{x^2}{64} +\frac{ y^2}{16} = 1[/tex]

Step-by-step explanation:

a)

The vertices are located in the x-axis, so we have a horizontal ellipse.

The equation of an ellipse is given by:

[tex]\frac{(x - h)^2}{a^2} +\frac{ (y - k)^2}{b^2} = 1[/tex]

The coordinates of the foci and the vertices are given by:

Foci: [tex]F(h \pm c, k)[/tex]

Vertices: [tex]V(h\pm a, k)[/tex]

Comparing the coordinates with the values given, we have that:

h = 0, k = 0, c = 2, a = 4

To find the value of b we can use the following equation:

[tex]c^2 = a^2 - b^2[/tex]

[tex]4 = 16 - b^2[/tex]

[tex]b^2 =12[/tex]

So the equation of the ellipse is:

[tex]\frac{x^2}{16} +\frac{ y^2}{12} = 1[/tex]

b)

If the ellipse is centered at the origin, we have:

h = 0, k = 0

The major axis is 'a' and the other axis is 'b', so we have:

a = 8, b = 4.

So the equation is:

[tex]\frac{x^2}{64} +\frac{ y^2}{16} = 1[/tex]