Let x be the length of the small piece, so the long one will be 3x. We also know that the length of each beam is 10 ft.
Using this information we can set up the equation and solve for x:
[tex]3x+x=10 [/tex]
[tex]4x=10[/tex]
[tex]x= \frac{10}{4} [/tex]
[tex]x=2.5[/tex]
Remember that the long piece is 3x.
Now we only need to replace the value of x in the expression to get:
[tex]3(2.5) = 7.5[/tex]
We conclude that the long piece should be 7.5 ft.
