What is the length of the major axis of the ellipse?

In summary, an ellipse is a flattened circle with a constant sum of distances from any point on the curve to two fixed points. The major axis of an ellipse is the longest diameter, calculated using the formula 2a where a is the semi-major axis. The length of the major axis can change depending on the eccentricity of the ellipse. An ellipse is different from a circle in that it is elongated, has a longer major axis, and has an eccentricity between 0 and 1.
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19,443
10,022
An ellipse on the xy-plane has foci at (-41, 23) and (115, 42). The ellipse is tangent to the x-axis. What is the length of the major axis of the ellipse?
 
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The length of the major axis of an ellipse is the longest diameter that runs through the center of the ellipse and connects two opposite points on the ellipse called the vertices. In this case, the foci and the tangent point on the x-axis can be used to determine the length of the major axis.

Using the distance formula, we can calculate the distance between the two foci as follows:

d = √[(x2 - x1)^2 + (y2 - y1)^2]
= √[(115 - (-41))^2 + (42 - 23)^2]
= √[156^2 + 19^2]
= √24337
= 156.085

Since the ellipse is tangent to the x-axis, the distance between the foci is equal to the length of the major axis. Therefore, the length of the major axis of the ellipse is approximately 156.085 units.
 

Related to What is the length of the major axis of the ellipse?

1. What is an ellipse?

An ellipse is a geometric shape that resembles a flattened circle. It is defined as a closed curve in which the sum of the distances from any point on the curve to two fixed points (called foci) is constant.

2. What is the major axis of an ellipse?

The major axis of an ellipse is the longest diameter of the ellipse, passing through the center and connecting two opposite points on the boundary of the ellipse. It is also known as the longest axis or the major diameter.

3. How is the length of the major axis of an ellipse calculated?

The length of the major axis of an ellipse can be calculated using the formula 2a, where a is the semi-major axis. The semi-major axis is half of the major axis and is equal to the distance from the center of the ellipse to the furthest point on the ellipse in any direction.

4. Can the length of the major axis of an ellipse change?

Yes, the length of the major axis of an ellipse can change. It depends on the eccentricity of the ellipse, which is a measure of how elongated the ellipse is. A higher eccentricity results in a longer major axis, while a lower eccentricity results in a shorter major axis.

5. How is an ellipse different from a circle?

An ellipse and a circle are both closed curves, but an ellipse is elongated while a circle is perfectly round. The major axis of an ellipse is longer than the minor axis, while the diameter of a circle is the same throughout. Additionally, a circle has an eccentricity of 0, while an ellipse has an eccentricity between 0 and 1.

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