Question

Find one solution of x-5=0 in a Cartesian plane

Answer 1

The given eqn is 
x-5=0
x=5

The above eqn  in 2 variables is written as,
x+0*y=5
The above eqn represent a straight line on cartesian plain parallel to y-axis and at a distance of 5 units on the right side of the y-axis.

Answer 2

the line x-5 = 0 is parallel to y - axis and 5 units distance from the y axis.
x-5 = 0
x = 5
The line passing through (5,0)