If you add Natalie's age and Fred's age, the result is 39. If you add Fred's age to 4 times Natalie's age, the result is 84. Write and solve a system of equations to find how old Fred and Natalie are. Fred is ___ years old. Natalie is ___ years old.

On traditional maps, earth is represented in a flat plane, or by euclidean geometry. however, a globe is a more accurate model that comes from elliptical geometry. how does a globe represent the fact that there are no parallel lines in elliptical geometry? the equator is not parallel to any other latitudinal lines. the north and south poles are never connected by a geodesic. the geodesics connecting the north and south poles never intersect. the geodesics connecting the north and south poles intersect at both of the poles.