Why is x equals 5 a vertical line and y equals -5 a horizontal line?

Answer 1

10

Answer 2

-- Take a piece of graph paper.

-- Draw upon it a set of 'x' and 'y' axes.

-- Number some part of both axes.

-- With a pencil, draw dots at a few points where [ x = 5 ].

What do you notice about all the points where x=5 ?

All of the points where x=5 are the same distance from the y-axis.

Since the y-axis is a vertical line, all of the points where x=5 form

another vertical line, parallel to the y-axis.

-- With a pencil of a different color, draw dots at a few points where [ y = -5 ].

What do you notice about all the points where y=-5 ?

All of the points where y=-5 are the same distance from the x-axis.

Since the x-axis is a horizontal line, all of the points where y=-5 form

another horizontal line, parallel to the x-axis.