Answer:
3
Step-by-step explanation:
When two plane mirrors are placed side by side such that they make some angle, θ, with each other, the number of images, n, of an object placed close to and in front of these mirrors is given by;
n = (360 / θ) - 1 ------------(i)
From the question;
θ = 90° [since they stood making a right angle with each other]
Substitute this value into equation (i) as follows;
n = (360 / 90) - 1
n = 4 - 1
n = 3
Therefore, the number of images formed is 3