Classify the triangle by the side and angle Equilateral

Scalene , right

Scalene , obtuse

Isosceles, acute

scalene and right

Step-by-step explanation:

it's a scalene triangle because all the sides have different lenghts. it's also a right triangle because of the square indicating that the triangle has a 90 degree angle making it a right triangle.

Answer is A

Step-by-step explanation:

Use the the pythagorean theorem

x=√12²+5²

x=13