Answer:
B = 25°
C = 65°
D = 25°
Explanation:
The given parameters are;
The orientation of the two mirrors = At right angle to each other
The laser light is directed at one of the mirror
The measure of angle, A = 25°
The measures of angle B, C, and D are found as follows;
We have;
∠A = ∠B = 25°, by angle of incidence equals angle of reflection
∠B = 25°
∠B + ∠C = 90° by sum of the acute angles of a right triangle
25° + ∠C = 90°
∴ ∠C = 90° - 25° = 65°
∠C = 65°
∠E = ∠C = 65° by angle of incidence equals angle of reflection
∴ ∠E = 65°
Line 'L' is perpendicular to the second mirror, therefore, the angle between line 'L' and the second mirror = 90° = ∠E + ∠D
∠E + ∠D = 90°, by angle sum property
Therefore;
65° + ∠D = 90°
∴ ∠D = 90° - 65° = 25°
∠D = 25°