Respuesta :

9514 1404 393

Answer:

  • 6 shirts at $8
  • 3 shirts at $7

Step-by-step 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.