# 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 - Geometry

Sum

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.

#### Solution

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.

Concept: Converse of Pythagoras Theorem
Is there an error in this question or solution?

Share