Final answer:
The expression $58(w)(w + 8) for the cost of constructing a deck consists of three factors: the numerical factor 58, the variable w, and the binomial (w + 8).
Step-by-step explanation:
To determine how many factors are in the expression $58(w)(w + 8) provided by your friend for the cost of constructing a deck based on its width, we look at each part of the expression that is multiplied together. We have the number 58, the variable w, and the binomial (w + 8). Therefore, we have three distinct factors in this expression.