In a triangle ABC, DE is parallel to BC. If AB = 7.2 cm; AC = 9 cm; and AD = 1.8 cm; Find AE.
"
Given: In a triangle ABC, DE is parallel to BC.
AB = 7.2 cm; AC = 9 cm; and AD = 1.8 cm
To find: The length of AE
Answer
Given triangle ABC
DE is parallel to BC
AB = 7.2 cm; AC = 9 cm; AD = 1.8 cm; AE = ?
By Basic proportionality theorem corollary
$\frac{AD}{AB} = \frac{AE}{AC}$
So $AE = \frac{AD}{AB} \times AC$ = $\frac{1.8}{7.2} \times 9 $= 2.25$ cm Answer
AE = 2.25 cm
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