Answer:
[tex]k=13\ m[/tex]
Explanation:
Given:
From the given information by the laws of reflection we can deduce the distance of the first reflection of the back of the head of person in the rear mirror.
Distance of the first reflection of the back of the head in the rear mirror from the object head:
[tex]y'=2\times y[/tex]
[tex]y'=7\ m[/tex] is the distance of the image from the object back head.
Now the total distance of this image from the front mirror:
[tex]z=y'+x[/tex]
[tex]z=7+3[/tex]
[tex]z=10\ m[/tex]
So, the total distance of the image of the back of the head in the front mirror from the person will be:
[tex]k=x+z[/tex]
[tex]k=3+10[/tex]
[tex]k=13\ m[/tex]