Question

Use geometry words to describe a way to separate triangles into other triangles?

Answer 1

You could draw a line segment from any vertex of a triangle to the opposite side. This will create 2 triangle inside of the original triangle.

Answer 2

Let us suppose we have a triangle ABC as shown in the attached image.

Now, let us we draw a perpendicular line from the vertex A to the base BC. Let the line meets the base BC at D.

Then, this perpendicular line AD will separate the triangle ABC into two right angle triangle ADB and triangle ADC.