The answer for number one is 36 square units because the rectangular area is 24 sq un and the triangular area is 12 sq un so I added them to get 36 sq un. The second answer is 40 sq un because if you cut the shape into 2 shapes you get 2 equal trapezoids. Each trapezoid is 20 sq un so I multiplied it by two to get 40 sq un. The third answer is 20 because the side triangles are 2 sq un each and the square on the bottom is 16 sq un. By the way, sq un means square units lol.
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.