Question

In ∆LMN, l = 5, m = 13, n = 12 then complete the activity to show that whether the given triangle is right angled triangle or not.
*(l, m, n are opposite sides of ∠L, ∠M, ∠N respectively)

Activity: In ∆LMN, l = 5, m = 13, n = `square`

∴ l² = `square`, m² = 169, n² = 144.

∴ l² + n² = 25 + 144 = `square`

∴ `square` + l² = m²

∴By Converse of Pythagoras theorem, ∆LMN is right angled triangle.

Answer 1

In ∆LMN,

l = 5, m = 13, n = 12

∴ l² = 25, m² = 169, n² = 144.

∴ l² + n² = 25 + 144 = 169

∴ n² + l² = m² 

∴By Converse of Pythagoras theorem, ∆LMN is right angled triangle.