If a triangle has the angles (in degrees) 60, 2x, and x, what is x? What are the angles?

The angles of a triangle add up to 180 degrees. Therefore 60 + x + 2x = 180. 60+3x = 180 3x = 120 x = 40 The angles are 40, 60, and 80 degrees.

What is the concept of polymorphism?

An inherited object has a parent. When defining a parent object, it can be labelled as either the parent or itself, as the inherited object shares the parental properties within itself.

How did mathematicians solve the fundamental problem of the slope of a line tangent to a curve?

They measured the slope of a secant line of two points on a line as a limit which approached closer to a tangent line. As the points converged into one, the slope of the tangent was found.