# Example 5 - Chapter 6 Class 7 Triangle and its Properties

Last updated at Sept. 10, 2018 by Teachoo

Last updated at Sept. 10, 2018 by Teachoo

Transcript

Example 5 Determine whether the triangle whose lengths of sides are 3 cm, 4 cm, 5 cm is a right-angled triangle. We know that, Hypotenuse is the largest side. So, Hypotenuse = 5 cm Checking Pythagoras theorem, ใ(๐ป๐ฆ๐๐๐ก๐๐๐ข๐ ๐)ใ^2 = ใ(๐ต๐๐ ๐)ใ^2 + ใ(๐๐๐๐๐๐๐๐๐๐ข๐๐๐)ใ^2 ใ(๐ป๐ฆ๐๐๐ก๐๐๐ข๐ ๐)ใ^2 = ใ(5)ใ^2 = 25 ใ(๐ต๐๐ ๐)ใ^2 " + " ใ(๐๐๐๐๐๐๐๐๐๐ข๐๐๐)ใ^2 = ใ(3)ใ^2 + ใ(4)ใ^2 = 9 + 16 = 25 Since, L.H.S = R.H.S Pythagoras theorem is satisfied Hence, 3cm, 4cm, 5cm form sides of a right angled triangle. Since, L.H.S = R.H.S Pythagoras theorem is satisfied Hence, 3cm, 4cm, 5cm form sides of a right angled triangle. Since, L.H.S = R.H.S Pythagoras theorem is satisfied Hence, 3cm, 4cm, 5cm form sides of a right angled triangle.

Checking if triangle is right angled

Chapter 6 Class 7 Triangle and its Properties

Concept wise

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Davneet Singh

Davneet Singh is a graduate from Indian Institute of Technology, Kanpur. He has been teaching from the past 10 years. He provides courses for Maths and Science at Teachoo.