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system of equations amanda bought 9 shirts for a total of 69$ Tee shirts cost 7$ and long sleeve shirts cost 8$ how many of each type did she buy

User Bishop
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1 Answer

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Answer:

  • 6 shirts at $8
  • 3 shirts at $7

Explanation:

Let x and y represent the numbers of $8 and $7 shirts, respectively. Your system of equations can be written ...

x + y = 9

8x +7y = 69

Subtracting 7 times the first equation from the second gives ...

(8x +7y) -7(x +y) = (69) -7(9)

x = 6

Then y is ...

y = 9 -x = 9 -6 = 3

Amanda bought 6 tees costing $8 and 3 tees costing $7.

User Liuting
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