If the x-intercept of a focal chord of the parabola $y^2=8x+4y+4$  is 3, then the length of this chord is equal to _________.

Given curves is  $y^2=8x+4y+4$
 $\Rightarrow {(y-2)}^2=8(x+1)$
Focus (-1, 2)
(y–2) = m(x–1)
Put (3, 0) in the above line then m = –1 
Length of focal chord = 16