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Ex 6.4
Ex 6.4, 2 Deleted for CBSE Board 2023 Exams
Ex 6.4, 3 Important Deleted for CBSE Board 2023 Exams
Ex 6.4, 4 Deleted for CBSE Board 2023 Exams
Ex 6.4, 5 Important Deleted for CBSE Board 2023 Exams
Ex 6.4, 6 Important Deleted for CBSE Board 2023 Exams
Ex 6.4, 7 Important Deleted for CBSE Board 2023 Exams
Ex 6.4, 8 (MCQ) Important Deleted for CBSE Board 2023 Exams
Ex 6.4, 9 (MCQ) Deleted for CBSE Board 2023 Exams
Last updated at July 16, 2019 by Teachoo
Maths Crash Course - Live lectures + all videos + Real time Doubt solving!
Ex 6.4, 1 Let ABC ~ DEF and their areas be, respectively, 64 cm2 and 121 cm2 . If EF = 15.4cm, find BC. Given:- ABC ~ DEF ar ABC = 64 cm2 ar DEF = 121 cm2 EF = 15.4 cm To find : BC Solution :- Since ABC ~ DEF We know that if two triangle are similar , Ratio of areas is equal to square of ratio of its corresponding sides Hence, ( )/( )=( / )^2 Putting the values 64/121=( /15.4)^2 64/121= 2/(15.4)2 64/121 (15.4)2= 2 ((8 8)/(11 11)) (15.4)2= 2 82/112 (15.4)2= 2 (8/11 15.4)2= 2 8/11 15.4= BC = 8/11 15.4 BC = 8 1.4 BC = 11.2 Hence, BC = 11.2 cm