Let ∆ ABC ~ ∆ DEF and their areas be, respectively, 64 cm² and 121 cm². If EF = 15.4 cm, find BC

Solution:

We know that the ratio of the areas of two similar triangles is equal to the square of the ratio of their corresponding sides.

Here it is given that ΔABC ~ ΔDEF

Given, EF = 15.4 cm

Therefore, Area of ΔABC / Area of ΔDEF = (BC)²/(EF)²

64 cm² / 121 cm² = (BC)²/(15.4)²

(BC)² = [(15.4)² × 64] / 121

BC = (15.4 × 8) / 11

BC = 11.2 cm

☛ Check: NCERT Solutions for Class 10 Maths Chapter 6

Video Solution:

Let ∆ ABC ~ ∆ DEF and their areas be, respectively, 64 cm² and 121 cm². If EF = 15.4 cm, find BC

NCERT Class 10 Maths Solutions Chapter 6 Exercise 6.4 Question 1

Summary:

Let ∆ ABC ~ ∆ DEF and their areas be, respectively, 64 cm² and 121 cm². If EF = 15.4 cm, then the value of BC is 11.2 cm.

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