Q6 of 56 Page 6

Triangles ABC and DEF are similar. If area (Δ ABC) = 16 cm2, area (Δ DEF) = 25 cm2 and BC = 2.3 cm, find EF.

Given: ΔABC ~ΔDEF


area (Δ ABC) = 16 cm2


area (Δ DEF) = 25 cm2


BC = 2.3 cm


To find: The length of EF.


Theorem Used:


Area of similar triangle:


The ratio of the areas of two similar triangles are equal to the ratio of the squares of any two corresponding sides.


Explanation:


Since, ΔABC ~ΔDEF


Then by area of similar triangle theorem,




By taking square root,




EF = 2.875cm


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