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A parabola can be drawn given a focus of (4, -3) and a directrix of x=2 Write the equation of the parabola in any form​

User Vadirn
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Answer:

The equation of the parabola ( y +3)² = 4 ( x-3)

Explanation:

Step(i):-

we know that the focus of the parabola (h + a , k ) and directrix is x = h - a

Given

focus of the parabola (h + a , k ) = ( 4, -3 )

Equating h + a =4 ..(i)

and k =-3

Given directrix is x = 2

h - a =2 ..(ii)

Adding (i) and (ii) equations , we get

h + a + h-a = 4+2

2 h = 6

h =3

substitute h=3 in equation (i)

h + a =4

3 + a =4

a = 1

The length of Latus rectum 4a = 4(1) =4

Step(ii):-

The vertex ( h, k) = ( 3 , -3) and a = 1>0

Given directrix is x = h - a = 2 so the parabola axis is lie on X- axis and symmetric about x-axis

The equation of the parabola

( y - k )² = 4 a ( x - h )

( y - (-3))²= 4(1) ( x - 3 )

The equation of the parabola ( y +3)² = 4 ( x-3)

User Igor Benikov
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