You have to make sure it is a triangle by adding the smallest and the medium sides, if the result is greater than the bigger side then it is a triangle.
you then use the Pythagorean theorem to check if the triangle is a right triangle, acute, or obtuse. If = then it is a right triangle. If then it is an obtuse triangle. if then it is an acute triangle.
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9+64_100
70_100
70<100
in this case is greater than therefore, is it an obtuse triangle.
(-2,2) and (-2,-3) are the bottom vertices, since (3,-3) is the top you can tell that it is the upper left vertex since it lines up with (2,-3), so the fourth vortex would line up with (-2,2) and would therefore be C. (3,2)