We find the intersection of two tangents to a parabola.
As the x-coordinate of E is the same as the midpoint of C and D, we see that the median of the triangle ECD is parallel with the y-axis, which is the axis of symmetry of the ellipse.
Expressions
| Name | Input | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| Intersection |  |
 |
 |
 |
 |
 |
 |
 |
 |
| |
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|
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| |
| Midpoint | |
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