Parameters:
(1) height of ladder contact point above ground in feet
(2) length of the ladder
(3) angle of the ladder to the ground
length of the ladder required =
= (length of ladder to reach the contact point) + (required overhang above contact point)
length of the ladder in feet to reach a given contact point above the ground =
= (height of contact point) / (SIN(angle of the ladder in terms of PI))
recommended overhang of a ladder leaning against eaves: minimum 3 feet
angle of the ladder to the ground in terms of PI =
= (angle in degrees) / 180 * PI()
Appropriate angle of the ladder can be one of the following:
(1) from 70 to 75 degrees
(2) based on the ladder base being [(height)/4] feet from the vertical point to the contact point (which is about 76 degrees; height/3 would be about 71 degrees)
