When I know the ground level of the point A is 11268AHD And

Solution

for this question you better need to consider a simple triangle method to determine the distance between the point A and assumed point B\' onn the same level of the grond.

Assume three points AB\'B forms a trangle.

As the point A to be assumed on the ground with reference to that we take the distance between A and B\' as \'x\'.

The point B lies exactly in same line perpendicular to B\' but at a distance 3.268AHD below the point B\'

now as we know the angle and hypotense length (sloping distance) we can find the distance between A and B\'

the the point B\' is determined