A set of weights includes a`20`lb barbell and`6`pairs of weight plates. Each pair of plates weighs `30` lb. If`x`pairs of plates are added to the barbell, the total weight of the barbell and plates in pounds can be represented by `f(x)=30x+20.`
The function f(x) represents the total weight of the barbell and plates in pounds, where x is the number of pairs of plates added to the barbell.
Each pair of plates weighs 30 pounds, so when x pairs of plates are added, the total weight of the plates is 30x pounds.
The barbell itself weighs 20 pounds.
Therefore, the total weight of the barbell and plates is given by f(x) = 30x + 20.