I am looking for horizontal distance between 2 points. My slope distance is 153.97' and a vertical distance of 91degrees 32minutes 45seconds.

what is slope distance*cosineAngle?

This is a very odd vertical angle.

Are you measuring the vertical angle (from the horizon) where 90 degrees is vertically up,

or the zenith angle (from zenith, vertically up) where 91 degrees is just below the horizon?

A vertical angle of 91 degrees requires a special eye-piece/prism, and is past the vertical.

You may want to check the measurements.

To find the horizontal distance between two points, you can use trigonometry. The horizontal distance is obtained by finding the difference between the slope distance and the vertical distance.

1. Convert the vertical distance from degrees, minutes, and seconds to decimal form. Since there are 60 minutes in a degree and 60 seconds in a minute, you can convert the vertical distance as follows:
Vertical Distance = 91 degrees + (32 minutes / 60) + (45 seconds / 3600)

2. Calculate the horizontal distance by using the following formula:
Horizontal Distance = Slope Distance * Cos(Vertical Angle)

3. Convert the vertical angle from decimal degrees to radians since the trigonometric functions in most programming languages accept inputs in radians.
Vertical Angle (in radians) = Vertical Angle (in degrees) * π / 180

4. Multiply the slope distance by the cosine of the vertical angle to obtain the horizontal distance.

Let's plug in the values:
Slope Distance = 153.97 feet
Vertical Distance = 91 degrees 32 minutes 45 seconds

Vertical Distance (in decimal form):
= 91 + (32 / 60) + (45 / 3600)
= 91.5458 degrees

Vertical Angle (in radians):
= 91.5458 * π / 180
= 1.5983 radians

Horizontal Distance:
= 153.97 * cos(1.5983)
= 153.97 * 0.2031
= 31.31 feet

Therefore, the horizontal distance between the two points is approximately 31.31 feet.