SOLUTION: The load that can be supported by a rectangular beam varies jointly as the width of the beam and the square of its​ height, and inversely as the length of the beam. A beam 14

Algebra ->  Customizable Word Problem Solvers  -> Misc -> SOLUTION: The load that can be supported by a rectangular beam varies jointly as the width of the beam and the square of its​ height, and inversely as the length of the beam. A beam 14      Log On

Ad: Over 600 Algebra Word Problems at edhelper.com


    

Question 1041032: The load that can be supported by a rectangular beam varies jointly as the width of the beam and the square of its​ height, and inversely as the length of the beam. A beam 14 feet​ long, with a width of 6 inches and a height of 4 inches can support a maximum load of 900 pounds. If a similar board has a width of 8 inches and a height of 5 ​inches, how long must it be to support 1400 ​pounds?
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
W=kwh%5E2%2FL
Substituting to find k,
900=k%28%286%29%284%29%5E2%29%2F14
k=525%2F4
So then,
1400=%28525%2F4%29%28%288%29%285%29%5E2%29%2FL%29
L=%28525%2F4%29%28%288%29%285%29%5E2%29%2F1400%29
L=75%2F4ft