NumericalEasy1 mark
6(b)
In the given figure AB = 9 cm, PA = 7.5 cm and PC = 5 cm. [3] Chords AD and BC intersect at P.
Find the length of CD.
Topic: Similarity / scale factor
Previous-year question practice database
Answer
Exam answer
From:
ΔPAB ∼ ΔPCD
Corresponding sides are proportional:
PA/PC = AB/CD
Substitute:
7.5/5 = 9/CD
7.5 × CD = 45
CD = 45/7.5
CD = 6 cm
Answer:
CD = 6 cm.
Explanation
Once the triangles are proved similar, corresponding sides are in the same ratio. PA corresponds to PC and AB corresponds to CD.
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