RecycledCDs, Incorporated, offers a choice of 5 used CDs for $23, With each additional CD costing $7. Write a cost function for purchasing 5 or more CDs. What will the cost of buying 12 CDs be? Let x represent the number of CDs over 5.

-- Cost Function

Cost of buying 12CDs is $72

Step-by-step explanation:

Given

Solving (a): Cost Function

Let n represent CDs greater than 5

Substitute:

  and    

Open Bracket

Collect Like Terms

Solving (b): When n = 12

Substitute 12 for n in

Cost of buying 12 CDs is $72

i believe the answer is d.

hope it you! : d

plants store their excess carbohydrate in the form of starch so that it could be used as energy source later on. the excess carbohydrate is converted into starch in the plastid i.e. chloroplast & this process occurs in the presence of sunlight. it is an insoluble polymer of glucose which gets stored in cell organelles named as amyloplasts. in some plants, starch is also stored in roots and embryos.