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Question
Find the equation of the parabola whose vertex is O(0, 0) and focus at (–7, 0).
Solution
The vertex of the required parabola is (0, 0) and focus is at (–7, 0).
∴ its axis is along X-axis
∴ its equation is of the form y2 = 4ax ...(1)
Then the focus is (a, 0) which is given to be (– 7, 0)
∴ a = – 7
∴ by (1), the equation of the parabola is y2 = – 28x.
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