5000, would be your answer.
Answer:
Karen needs to spend $4.5 to buy new hair bands.
Step-by-step explanation:
Given:
Hair bands Karen have = 3
cost of 8 hair bands = $1
Total Hair bands she require = 39
Hence Number of of new hair bands require = Total Hair bands she require - Hair bands Karen have = 39 -3 = 36
we need to find how much money she need to spend to buy new hair bands.
cost of 8 hair bands = $1
Cost of 36 hair bands = money need to spend on hair bands
By using Unitary method we get;
Money spend on new hair bands = 
Hence,Karen needs to spend $4.5 to buy new hair bands.
Notice the table of values, thus let's pick two points from it, to check what the slope may be,

I support this answer it’s correct I see it ♥️