If 12 squared + b squared = 15 squared what is b squared.

What is the value of x in the diagram below?

According to modern science, earth is about 4.5 billion years old and written human history extends back about 10,000 years. suppose the entire history of earth is represented with a 10-meter-long timeline, with the birth of earth on one end and today at the other end.

Draw a scaled copy of the circle using a scale factor of 2