20 what decimal does this model represent? explain.

The model represents the decimal 73.

Step-by-step explanation:

The model is 10x10. You must count the blue blocks. The number of blue blocks is 73, therefore it represents the decimal 73. (Hope this helped!)

point a is the center of the circle that passes through points e, f, and g and the center of the circle that passes through points x, y, and z.