# If Abc and Def Are Two Triangles Such that δAbc ≅ δFde and Ab = 5cm, ∠B = 40° - Mathematics

MCQ

If ABC and DEF are two triangles such that ΔABC $\cong$ ΔFDE and AB = 5cm, ∠B = 40°

#### Options

• DF = 5cm, ∠F = 60°

• DE = 5cm, ∠E = 60°

• DF = 5cm, ∠E = 60°

• DE = 5cm, ∠D = 40°

#### Solution

It is given that  ΔABC $\cong$ ΔFDE and AB = 5 CM . ∠B = 40 , and ∠A = 80°

So AB = FD and  ∠C = ∠E

Now, in triangle ABC,

∠A +∠B +∠C = 180°

⇒ 80 + 40 + ∠C = 180°

⇒ ∠C = 60°

Therefore,

DF = 5cm, ∠E = 60°

Is there an error in this question or solution?

#### APPEARS IN

RD Sharma Mathematics for Class 9
Chapter 12 Congruent Triangles
Q 12 | Page 86