Q5 of 47 Page 10

If AB, AC, PQ are tangents and AB = 5 cm, find the perimeter of ΔAPQ.

Given: AB, AC, PQ are tangents.


AB = 5 cm


To find: Perimeter of ΔAPQ.


Theorem Used: The length of two tangents drawn from an external point are equal.


Explanation:



As A is an external point and AP and AQ are two tangents drawn from it.


AB = AC … (1)


As Q is an external point and QC and QX are two tangents drawn from it.



QC=QX … (2)


As P is an external point and PB and PX are two tangents drawn from it.



PB = PX … (3)



AB = AC = 5cm


Perimeter of ΔAPQ = AP+PQ+QA


= AP+(PX+QX) +QA


From (2) and (3).


= AP+PC+QC+QA


= AC+AB



=5+5


=10cm


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