math help
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- xcarlx0
first of all, no offense but you should of learned this in 6th grade.
second of all, you do not need the Pythagorean theorem to calculate the dimensions of stairs, you need to calculate the rise and run if each tread. a good rule of thumb is 7" rise, 11" run (for each tread, (assuming imperial) divide the finish floor to finish floor height by 7 to find the number of risers, the stair well length by 11 (minus space for landings) to find the number of treads, draw it out on graph paper (or even sketch up)
there is the length of your stringer.
i use to do this for a living, trust me on it.
- ribit0
I'd do all this on a drawing and just measure it...
- FredMcWoozy0
google can process math problems I believe.
- jteore0
~ ~ c===========3
- drgss0
IQ = sqrt(139.94) = 11.82
- monNom0
If you're looking for the slope (angle) you need trigonometry, not pythagorus.
a^2 + b^2 = c^2 gives you the length of the hypotenuse (long side)
trig will calculate the angle:
cosine of angle = opposite/adjacent
on a calculator you would go: opposite/adjacent = 72/120 = 0.6
the inverse cosine of 0.6
= 53.13degof course stairs they usually just say 12 over 8 or whatever and don't bother with the actual angle.
- drgss0
cosine of angle = adjacent/hypotenuse
sit down, monNom, D minus