"let two plane mirrors are inclined at an angle theta.
total deviation produced from two inclined plane mirror after two successive reflection is given by delta=360-2theta
the number of images formed n=(360/theta)-1, if (360/theta) is even integer..
if (360/theta) is odd integer, the number of images formed n=(360/theta)-1 when the object is kept symmetrically, and n=(360/theta) when object is kept asymmetrically..
if (360/theta) is a fraction, the number of images formed is equal to its integral part..
how do we get these relations"

we take succesive images of every image on its opposite mirror till the image finally ends to the other side of the opposite mirror...

u should end up getting a arithmetic series for the angle for the image formed first 1 and i.this angle should not exceed 180 degree as the image will go behind the mirror..then the total no will be added for both to get the formula.

step-by-step explanation: h: (- 3, 6)

m: (1, - 2)

o: (7, 6)

r: (- 9, - 2)

midpoint of hm: (- 1, 2)

midpoint of or: (- 1, 2)

therefore, b is the midpoint of both diagonals bisect each other !

to prove the diagonals are perpendicular, show that the product of the slopes = - 1