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parametric question (1 Viewer)

blakwidow

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Find the eqn of the parabola, with vertex at the origin, the x-axis vertical and the line x + y + 2 = 0 is a tangent to it

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pLuvia

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Use the general formula of a parabola
x2=4ay or y2=4ax

Since it states that the y axis is a tangent then it must mean that the parabola is sideways hence
y2=4ax

Now you are told that x+y+2=0 is a tangent, sub that into your general equation of a parabola then since it only touches the parabola at one point the discriminant equals to 0 then solve for a, and voila
 

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