Question

A ray of light is sent along the line x + y = 1, after being reflected from the line y – x = 1 it is again reflected from the line y = 0, then the equation of the line representing the ray after second reflection may be given as

• A. x + y = 1
• B. x – y = 1
• C. y – x = 1
• D. x + y + 1 = 0
  

Answer 1

The correct option is B x – y = 1

Since, incident ray is perpendicular to the line mirror y - x = 1, so after reflection reflected ray goes back and intersect x-axis at A.

whose equation is x-y=1