In the given figure, ΔOAB ~ ΔOCD. If AB = 8 cm, BO = 6.4 cm, OC = 3.5 cm and CD = 5 cm, find (i) OA (ii) DO.
(i). Given that, AB = 8 cm
BO = 6.4 cm,
OC = 3.5 cm
& CD = 5 cm
∆OAB ∼ ∆OCD
When two triangles are similar, they can be written in the ratio as
Substitute gave values in the above equations,
⇒ 
⇒ OA = 5.6
Thus, OA = 5.6 cm
(ii). Given that, AB = 8 cm
BO = 6.4 cm,
OC = 3.5 cm
& CD = 5 cm
∆OAB ∼ ∆OCD
When two triangles are similar, they can be written in the ratio as
Substitute gave values in the above equations,
⇒ 
⇒ DO = 4
Thus, DO = 4 cm
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