In the given figure, find the perimeter of ΔABC, if AP = 12 cm.

1

CBSE 10th Class Mathematics
Past year question paper
Year 2020
SET 1, Code Number – 30/5/1
Question Number – 24 [b]
perimeter problem
triangle perimeter

Perimeter of ΔABC = AB + BC + AC
= AB + BD + CD + AC
= AB + BP + CQ + AC
[Since BD = BP and CD = CQ]
= AP + AQ
= 2AP [AP = AQ, Tangents drawn
from external point]
= 2 × 12

Perimeter of ΔABC = AB + BC + AC

= AB + BD + CD + AC

= AB + BP + CQ + AC

[Since BD = BP and CD = CQ]

= AP + AQ

= 2AP [AP = AQ, Tangents drawn

from external point]

= 2 × 12

= 24 cm