Calculate the horizontal length (HL) from a slope in degrees and the slope length (SL).
Calculator uses the cosine function "The cosine of an angle in a right angled triangle is the ratio that multiplies the slope length and results in the horizontal length."
Formula: HL = cosine(degrees * π ÷ 180) * SL
Example calculation
slope angle = 18.2°
length of slope line = 14' 11" converted to inches --- 12 * 14 + 11 = 179"
converting the degrees to radians
18.2 *
π/
180 = 0.3176499
using the cosine function to get the ratio
cos(0.3176499) = 0.94997
multiplying the slope length by the cosine ratio
179 * 0.94997 = 170" (rounded) = 14' 2"
The horizontal distance is 14' 2"