What is always used to find a coordinate?

The X and Y axis, are used to find a coordinate, because when you are looking on the y-axis, you are looking up (y to the sky/vertical),and on the X axis you are looking horizontally and finding both your coordinates that way. You will get two numbers in the end, and the x coordinate always goes first followed by the y. (x-coordinate, y-coordinate) Usually they are labeled with numbers on both the x and the y axis.

a is the answer i believe.

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