Find the equation of the parabola, which is symmetric about the y-axis and passes through the point P(2, -3).
The equation of a parabola with vertex at the origin and symmetric about the y-axis is
x2 = 4ay
Since point P(2,-3) passes through above parabola we can write,
22 = 4a(-3)
• 4 = -12a
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Therefore, the equation of a parabola is
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• 
• 3x2 = -4y
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