i think that A pair of an input value and its corresponding output value is called an ordered pair and can be written as (a, b). In an ordered pair the first number, the input a, corresponds to the horizontal axis and the second number, the output b, corresponds to the vertical axis.
We can thus write our values as ordered pairs
(0, 0) - This ordered pair is also referred to as the origin
(1, 2.5)
(2, 5)
(3, 7.5)
These ordered pairs can then be plotted into a graph.
