Answer :
Explanation:
Pythagoras theorem states that, The square of the longest side of the triangle is equal to the sum of the other two sides of the triangle.
i.e a² + b² = c² [where c is the longest side of the triangle and a and b are the other two sides]
If a² + b² < c² then the triangle is obtuse.
If a² + b² > c² , then the triangle is acute.
If a² + b² = c² , then the triangle is right angled.
Let's solve,
From the given diagram, Longest side (c) is 7 and the other two sides (a and b) are√31 and √18 .
Using Pythagoras theorem,
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Since, a² + b² = c². Therefore The given triangle is right angled.