<span>When given 3 triangle sides, to determine if the triangle is acute, right or obtuse:
</span>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<span>
if sum < 3rd side² Obtuse Triangle
1) 1,296 2,401 3,600
2) Sum = 3,697
3) </span><span>3,697 is greater than 3,600
Therefore, the triangle is acute.
Source:
http://www.1728.org/triantest.htm
</span>
Step-by-step explanation:
Equation: 
First step:

Second step:

Third step:

Fourth step:

The ANWSER is B hope this helps
To blurry if you need help just contact me
Answer:
it is D
Step-by-step explanation:
For knowing it, it is necessary to draw straight line above the triangle from the middle of the sides, forming a 90° degree angle. But as they are already drew, it is easier