Question

Determine if the triangle with the given sides is acute, obtuse, or right. 36, 49, 60

Answer 1

When given 3 triangle sides, to determine if the triangle is acute, right or obtuse:
1) Square all 3 sides.
2) Sum the squares of the 2 shortest sides.
3) Compare this sum to the square of the 3rd side.

if sum > 3rd side²   Acute Triangle
if sum = 3rd side²   Right Triangle
if sum < 3rd side²   Obtuse Triangle

1) 1,296   2,401   3,600
2) Sum = 3,697
3) 3,697 is greater than 3,600
Therefore, the triangle is acute.

Source:
http://www.1728.org/triantest.htm