Since it is a horizontal parabola.its equation has the for $\"\"$ .

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We have only two points.so there are two solutions.Say the points

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$\"\"$

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$\"\"$

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The length of the latus rectum $\"\"$ so a $\"\"$

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Then the equation becomes \ \

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$\"\"$

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Plug the points into the equation.

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$\"\"$

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$\"\"$

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Solve the system for b and c . \ \

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$\"\"$

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$\"\"$

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$\"\"$ ------------>(1)

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$\"\"$

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$\"\"$

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$\"\"$ ------------->(2)

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Add (1) and (2) \ \

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$\"\"$

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$\"\"$

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_________

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$\"\"$

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Substitute the value $\"\"$ in (2).

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$\"\"$

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$\"\"$

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Plug the values into the equation

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$\"\"$

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The equation of the parabola is $\"\"$ .

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