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Question
See the given figure. DE || BC. Find EC.
Solution
Let EC = x cm
It is given that DE || BC.
By using basic proportionality theorem, we obtain
`("AD")/("DB") = ("AE")/("EC")`
`(1.5)/3 = 1/x`
By cross-multiplication, we have
x = `(1xx3)/1.5`
x = `(1xx3xx10)/15`
∴ x = 2 cm
EC = 2 cm
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