Question

Calculate the distance between A (5, -3) and B on the y-axis whose ordinate is 9.

Answer 1

We know that any point on y-axis has coordinates of the form (0, y).
Ordinate of point B = 9
Since, B lies of y-axis, so its co-ordinates are (0, 9).
AB = `sqrt((0 -5)^2 + (9 + 3)^2)`
= `sqrt(25 + 144)`
= `sqrt(169)`
= 13 units