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.
Using the Pythagorean Theorem,
radius^2 = 40^2 + 9^2
radius^2 = 1,600 + 81
radius^2 = 1,681
radius = 41
2(z - 5) + (z - 8) =
= 2z - 10 + z - 8 =
= 2z + z - 10 - 8 = <u>3</u><u>z</u><u> </u><u>-</u><u> </u><u>1</u><u>8</u> ← the end