A light ray gets reflected from the line $x=-2$. If the reflected ray touches the circle $x^2+y^2=4$ and the point of incidence is $(-2,-4)$, then the equation of incident ray is

Any tangent of circle $x^2+y^2=4$ is $y=mx\pm 2\sqrt{1+m^2}$

If it passes through $(-2,-4)$ then

${(2m-4)}^2=4(1+m^2)$

$\Rightarrow 4m^2+16-16m=4+4m^2$

$\Rightarrow m=\infty ,m=\frac{3}{4}$

Hence slope of reflected ray is $3/4$

Slope of incident ray is $\frac{-3}{4}$

Incident ray is $y+4=\frac{-3}{4}(x+2)$

$3x+4y+22=0$