SOLUTION: Please explain all steps 8th grade algebra 1 You are buying gifts for 10 people. You decide to buy each person either a CD or a DVD. A CD costs $ 12 and a DVD costs $20.

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Question 917414: Please explain all steps 8th grade algebra 1
You are buying gifts for 10 people. You decide to buy each person either a CD
or a DVD. A CD costs $ 12 and a DVD costs $20.

A. Let c = the number of CDs you decide to buy. What is an expression in
terms of c for the number of DVDs you buy?

b. What is an expression in terms of c for the cost of the CDs? For the cost
of the DVDs?

c. Write and simplify an expression in terms of c for the total cost of all
the gifts you buy. What properties of real numbers did you use to simplify the
expression?

Please show all steps I need to teach this to my daughter who struggles in
algebra.
Thank you so much! Need all step please!!!!
Answer by JoelSchwartz(130) (Show Source):
You can put this solution on YOUR website!
a
c+d=10
c=number of cds purchased
d=number of dvds purchased
We know that you are buying one gift per person and their are ten people. That means that their are ten gifts you will be buying. You also know that you are either buying a cd or a dvd. We know that the number of cds plus the number of dvds has to equal ten. The equation in terms of c is going to look like. d=10-c
b
12c=total cost of the cds
20(10-c)=total cost for the dvds

c
t=total cost for the cds and dvds
t=12c+20d
t=12c+20(10-c)
t=12c+200-20c
The distributive property is used.
Commutative Property of Addition is also used.