Question

A parabola can be drawn given a focus of (8, 6) and a directrix of x=4. Write the equation of the parabola

Answer 1

Answer:

The equation of the Parabola

 (y - 6 )² = 8 (x -6)

Step-by-step explanation:

Step(i):-

Given directrix  x = 4

we know that    x = h - a = 4

               h -a =  4  ...(i)

Given Focus  = ( 8,6)

we know that the Focus of the Parabola

         ( h + a , k ) = ( 8,6)

   comparing  h + a = 8 ...(ii)

                  k = 6

solving (i) and (ii) and adding

   h - a + h+ a = 8 +4

           2 h = 12

              h =6

   Put h = 6 in equation (i)

  ⇒     h - a =4

  ⇒   6 - 4 = a

  ⇒      a = 2

Step(ii):-

The equation of the Parabola ( h,k) = (6 , 6)

( y - k )² = 4 a ( x - h )

(y - 6 )² = 4 (2) (x -6)

(y - 6 )² = 8 (x -6)