1971 AHSME Problems/Problem 19
Problem
If the line intersects the ellipse exactly once, then the value of is
Solution
Plug in into the ellipse's equation to find the intersection points: After simplifying, we have a quadratic in :
Because there is only one intersection point, then the quadratic has only one solution. This can only happen when the discriminant is 0.
Solving, we find
-edited by coolmath34
See Also
1971 AHSC (Problems • Answer Key • Resources) | ||
Preceded by Problem 18 |
Followed by Problem 20 | |
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