Ross calculated the missing side length of the triangle F.
Solution:
Let us first define the Pythagoras theorem.
Pythagoras theorem:
In right triangle, square of the hypotenuse is equal to the sum of the squares of the other two sides.
So, it is clearly define that Pythagoras theorem is applied for right triangles only.
Right angle is indicated by the symbol "L".
In the given triangles,
E is acute angled triangle.
G is obtuse angled triangle.
H is acute angled triangle.
F is right angled triangle.
Therefore, Pythagoras theorem can be applied only for triangle F.
So Ross calculated the missing side length of the triangle F.