Respuesta :

lulbodynatalie
This is because two angles are zero and top is a straight line, and a line is 180 degrees!

hopes this helps :)
marinl5918

Answer:

Step-by-step explanation:

Because every triangle that can ever be made has three sides, you can open up the triangle so that it becomes a straight horizontal line. A horizontal line is also 180 degrees which is why this idea works with triangles.