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 = \[\boxed{12}\]

∴ l² = \[\boxed{25}\], m² = 169, n² = 144.

∴ l² + n² = 25 + 144 = \[\boxed{169}\]

∴ \[\boxed{n^2}\] + l² = m² 

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