Let (0, b) be the point on the y-axis whose distance from line x/3 + y/4 =1 is 4 units.
The given line can be written as
4x + 3y – 12 = 0 ………………….… (1)
On comparing equation (1) to the general equation of line Ax + By + C = 0, we obtain
A = 4, B = 3, and C = –12.
It is known that the perpendicular distance (d) of a line Ax + By + C = 0 from a point

Therefore, if (0, b) is the point on the y-axis whose distance from line x/3 + y/4 =1 is 4 units, then:
