The answer is below.
Work Step by Step
I would describe it using the analogy of a map. In a city, we could define a starting point (the origin). Perhaps, in order to go to the bank, you go three blocks right and two blocks up. Thus,connecting this analogy to coordinate geometry, we see that if we define an origin, we can identify certain points in reference to that origin. Thus, instead of saying to go three units right and two units up, we could say that the bank is located at the point (3,2).