It seems to me that 2 shelves with 20 books each would work as well as 20s with 2b, 4s with 10b, 10s with 4b, 5s with 8b and 8s with 5b. is this correct?

A80-foot piece of siding is cut into three pieces so that the second piece is four times four times as long as the first piece and the third piece is five times as long as the first piece. if x represents the length of the first piece, find the lengths of all three pieces.

Let the closed interval [a , b] be the domain of function f. the domain of f(x - 3) is given by (a) the open interval (a , b) (b) the closed interval [a , b] (c) the closed interval [a - 3 , b - 3] (d) the closed interval [a + 3 , b + 3]

Express in the simplest form: (x^2+9x+14/x^2-49) / (3x+6/x^2+x-56)