NCERT Exemplar Solutions
Class 7 - Mathematics - Unit 6: Triangles - Problems and Solutions
Question 146

Question. 146

Triangles DEF and LMN are both isosceles with DE = DF and LM = LN, respectively. If DE = LM and EF = MN, then, are the two triangles congruent? Which condition do you use? If ∠E = 40°, what is the measure of ∠N?

Answer:

Yes, congruent by SSS. ∠N = 40°

Detailed Answer with Explanation:

DE = LM, EF = MN, DF = LN, hence congruent by SSS. So corresponding angles equal ⇒ ∠E = ∠N = 40°.

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