Q2 of 168 Page 5

In Fig. 4.177, . If BC = 10 cm, PQ = 5 cm, BA = 6.5 cm and AP = 2.8 cm, find CA and AQ. Also, find the area () : area ().

We have,


ΔACB ~ ΔAPQ


Then, AC/AP = CB/PQ = AB/AQ[Corresponding parts of similar Δ are proportional]


Or, AC/2.8 = 10/5 = 6.5/AQ


Or, AC/2.8 = 10/5 and 10/5 = 6.5/AQ


Or, AC = 5.6cm and AQ = 3.25cm


By area of similar triangle theorem


Area of ΔACB/Area of ΔAPQ = BC2 /PQ2


= (10)2/(5)2


= 100/25


= 4 cm


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