Answer:
1: Obtuse
2: A
Explanation:
One angle is 57° and another is 12°. If we add them, we get 69. Subtract 69 from 180 to get missing angle: 180-69=111
the missing angle is 111°. We know this is not a right triangle because those have a 90° angle. Since one angle is bigger than 90 (111°), the triangle is obtuse.
For the second one, we see that the first triangle is equal on all sides, so it is equilateral. The second triangle has just two equal sides, so it is isosceles. The thrid one is different side length on all of them, so it is scalene. the answer is A.