Question

It is given that the ∆ABC ≅ ∆FDE, and AB = 4 cm, B = 40° and E = 60°,

then which of the following is true?

(a) DE = 4 cm, A = 80° (b) DE = 4cm, C = 80°

(c) DF = 4 cm, A = 80° (d) DF = 4cm, C = 80°​

Answer 1

Step-by-step explanation:

Two triangles are congruent if their corresponding sides are equal in length and their corresponding angles are equal in size.

In the first option, DF=5 cm but ∠F is not equal to 60

∘

.

In the third and the fourth options, the length of DE



=5cm, since it is not defined.

In the second option, DF=5cm and ∠E=60

∘

is satisfied.

Answer 2

Answer:

explanation:- ∆ABC= ∆FDE

therefore,AB=FD,BC=DE,AC=FE

A=F,B=D,C=E

AB=4cm=FD

B=40°=D

E=60°=C.

60°+40°=100°

therefore,remaining angle is of 80°.

remaining angles are A and F

A=F

therefore,A=F=80°

ANS:-(C) DF=4cm,A=80°.