Question

Three sides of a triangle are a,3a, and root 10a.Find the measurement of angle opposite to the largest side

Answer 1

We know that
In a right triangle, the sum of the squares of the any two sides is equal to the the square of the third side. 
Observe that
a²+(3a)² = (side)²
⇒ a²+9a² = (side)²
⇒10a² = (side)²
side = √10 a

Therefore, the triangle is a right triangle.

The angle opposite to the the largest side is 90 degrees

Answer 2

Answer:

We know that

In a right triangle, the sum of the squares of the any two sides is equal to the the square of the third side.  

Observe that

a²+(3a)² = (side)²

⇒ a²+9a² = (side)²

⇒10a² = (side)²

side = √10 a

Therefore, the triangle is a right triangle.

The angle opposite to the the largest side is 90 degrees