Question

pls answer this
class 10th...Triangles chapter​

Answer 1

Answer:

According to congruence ABC=DEF

So, BC=EF

Answer 2

Answer:

• The measure of EF is 2.8 cm.

Step-by-step explanation:

Given,

• ΔABC ~ ΔDEF.

Hence,

area of ΔABC / area of ΔDEF = BC² / EF²

[∵ In two similar triangles, ratio of their area is equal to the squares of ratio of their corresponding sides.]

⇒ 9 cm² / 16 cm² = (2.1)² / EF²

⇒ 9/16 = 4.41/EF²

⇒ 0.56 = 4.41/EF²

⇒ EF² = 4.41/0.56

⇒ EF² = 7.87

⇒ EF = √7.87

⇒ EF = 2.8 cm

∴ The measure of EF is 2.8 cm.