During the sale shirts were marked down 20 percent to $20. What was the regular price of the shirts (the price before the sale)

the 3rd on is correct

step-by-step explanation:

why are you giving so many marks make your marks less and make a question list so that i can understand your question very nicely

answer: c

substitute in the values.

for a:

f(0) = 0 + 9

f(0) = 9

a is a solution.

for b:

f(7) = 14 + 9

f(7) = 23

b is a solution.

for c:

f (3) = 6 + 9

f(3) = 15

c is not a solution. it's supposed to be 14.

for d:

f(2) = 4 + 9

f(2)= 13

d is a solution.