PB6. In Fig. 6.33, PO and RS are two mirrors placedparallel to each other. An incident ray AB strikesthe mirror PQ at B, the reflected ray moves alongthe path BC and strikes the mirror RS at C andagain reflects back along CD. Prove thatABICD.Fig. 6.33 -

PB6. In Fig. 6.33, PO and RS are two mirrors placedparallel to each ot

1.	PB6. In Fig. 6.33, PO and RS are two mirrors placedparallel to each other. An incident ray AB strikesthe mirror PQ at B, the reflected ray moves alongthe path BC and strikes the mirror RS at C andagain reflects back along CD. Prove thatABICD.Fig. 6.33 -
Answer» Solution:Let draw BM ? PQ and CN ? RS.Given that� PQ \|\| RS so that� BM \|\| CNUse the property of Alternate interior angles?2 = ?3 �� (1)?ABC = ?1 + �?2But ?1 =� ?2 so that?ABC = ?2 +� ?2?ABC = 2?2Similarly?BCD = ?3 +� ?4But ?3 =� ?4 so that? BCD = ?3 +� ?3? BCD = 2?3From equation first?ABC = ?DCBThese are alternate angles so that AB \|\| CDHence proved