1 - x + 2x ^ 2 + x ^ 3 + (3x ^ 4)/4

factorise it.

okay, so I have attached the solution, I tried my best to solve it and here's the answer I'm getting, hope that helps...

Here we can see that there has to be a single unknown variable and using that variable we have to create an equation. That equation will ultimately help us to find the exact value of the variable. This way we can easily reach the answer that is asked in the question.
Let us assume the length of the first piece = x
Length of the second piece = 2x
Length of the third piece = 6x
Now we can get to the equation
x + 2x + 6x = 180
9x = 180
x = 180/9
  = 20
So the length of the first piece of the board is 20 feet.I hope i have explained the problem to your satisfaction and understanding.