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1. how do i do this ive been trying for so long

the parabola has equation y^2 = 24x
with a focus of (6,0)
and a directrix of x + 6 =0

points q and p are both on the parabola and are 9 units away from the directrix of the parabola

find the exact length of pq stating your answer as a surd

ive ended up somehow with a triangle but have no idea what to do
help would be really appreciated
2. (Original post by jumblebumble)
how do i do this ive been trying for so long

the parabola has equation y^2 = 24x
with a focus of (6,0)
and a directrix of x + 6 =0

points q and p are both 9 units away from the directrix of the parabola

find the exact length of pq stating your answer as a surd

ive ended up somehow with a triangle but have no idea what to do
help would be really appreciated
are p and q on the parabola?
3. (Original post by Pheylan)
are p and q on the parabola?
sorry, yes,
4. (Original post by jumblebumble)
how do i do this ive been trying for so long

the parabola has equation y^2 = 24x
with a focus of (6,0)
and a directrix of x + 6 =0

points q and p are both on the parabola and are 9 units away from the directrix of the parabola

find the exact length of pq stating your answer as a surd

ive ended up somehow with a triangle but have no idea what to do
help would be really appreciated

draw the parabola sketch and the directrix to see this
the x values of p and q are gona be 3 since they are 9 units away from the line x=-6
so u simply plug in x=3 in the equatiion y^2=24x to get (+/- 6root2) those are the two y values
so the distance is gona be 2 x 6root2 which is 12root2
hope u get it now
the sketch should help u understand
5. (Original post by jumblebumble)
sorry, yes,

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