DE ∥ BC of ΔABC where D and E are two points on AB and AC, respectively. If AD = 5 cm, DB = 6 cm, and AE = 7.5 cm, calculate the length of AC.
WBBSE
Class X
Mathematics
Similarity
02 Mark
2022
Given
- AD = 5 cm
- DB = 6 cm
- AE = 7.5 cm
AB = AD + DB
or, AB = 5 cm + 6 cm
or, AB = 11 cm
(AD / AB) = (AE / AC) [Since DE || BC]
or, (5 / 11) = (7.5 / AC)
or, 5 × AC = 7.5 × 11
or, AC = (7.5 × 11) / 5
or, AC = 82.5 / 5
or, AC = 16.5 cm
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