I need the answer to the image attached

D

Step-by-step explanation:

let y = f(x) and rearrange making x the subject

y = ( multiply both sides by x )

xy = 8 ( divide both sides by y )

x =

Change y back into terms of x

(x) = ← with restriction x ≠ 0 → D

if you are saying purchasing 3 social media ads and one newspaper ad counts as one purchase then there are:

6 purchases

if you are asking how many of each then:

18 social media ads

6 newspaper ads