Calculate the distance between A(7, 3) and B on the x-axis whose abscissa is 11.

We know that any point on x-axis has co-ordinates of the form (x, 0).

The abscissa of point B is 11.

So, the point B is (11, 0).

Distance between the given points = $\sqrt{(x$2 - x1)^2 + (y2 - y1)^2}

Distance between A(7, 3) and B(11, 0):

$= \sqrt{(11 - 7)^2 + (0 - 3)^2}\\[1em] = \sqrt{4^2 + (- 3)^2}\\[1em] = \sqrt{16 + 9}\\[1em] = \sqrt{25}\\[1em] = 5 \text{ units}$

Hence, the distance between A(7, 3) and B(11, 0) is 5 units.