The equation d = 22.5n + 27.5 represents the amount of money, in dollars, that Kathryn earns for each sale she makes. The variable n represents the number of items sold, and the variable d represents the total amount of money earned. What is the number of items Kathryn must sell in order to earn $500?

A)10

B)17

C)21

D)23

b

step-by-step explanation:

the equation of a line in point- slope form is

y - b = m(x - a)

where m is the slope and (a, b) a point on the line

calculate m using the slope formula

m = (y₂ - y₁ ) / (x₂ - x₁ )

with (x₁, y₁ ) = (0, 4) and (x₂, y₂ ) = (3, - 5) ← 2 points on the line

m = = = - 3

with m = - 3 and (a, b) = (3, - 5), then

y - (- 5) = - 3(x - 3), that is

y + 5 = - 3(x - 3) → b

x= cost per bracelet

number of bracelets * x + shipping charge = total cost

so

9x+9=72

the one below it is a function