Discover new perspectives and gain insights with IDNLearn.com's diverse answers. Find in-depth and trustworthy answers to all your questions from our experienced community members.
Given:
The sides of a triangle are 3 cm, 5 cm, 7 cm.
To find:
The angle classification of the given triangle.
Solution:
Let a,b,c are the three sides of a triangle ABC, where c is the longest side.
1. Triangle ABC is acute, if [tex]c^2<a^2+b^2[/tex].
2. Triangle ABC is acute, if [tex]c^2=a^2+b^2[/tex].
3. Triangle ABC is acute, if [tex]c^2>a^2+b^2[/tex].
The sum of square of two smaller sides is
[tex]3^2+5^2=9+25[/tex]
[tex]3^2+5^2=34[/tex]
In the given triangle 7 cm is the longest sides. So,
[tex]7^2=49[/tex]
It means,
[tex]7^2>3^2+5^2[/tex]
Since [tex]c^2>a^2+b^2[/tex], therefore, the triangle ABC is an acute triangle.