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Manuel and rita bought cds at the music store. rita's cds originally cost three times more than manuel's cds, but she received a $9 discount. if rita spent $21 total, which equation can be used to find the amount manuel spent

User Scruffers
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2 Answers

3 votes
3m - 9 = 21 <=== ur equation
3m = 21 + 9
3m = 30
m = 30/3
m = 10 <== ur solution
User Ken Lee
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4 votes

Answer with Step-by-step explanation:

Let cost of Manuel's cds=m

Rita's cds originally cost three times more than Manuel's cds, but she received a $9 discount.

i.e. Rita's cds cost=3m-9

Rita spent $21 total.

i.e. 3m-9=21

Adding 9 on both sides, we get

3m=30

Dividing both sides by 3, we get

m=10

Hence, equation which can be used to find the amount Manuel spent is:

3m-9=21

User Arychj
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