Given:
Let x be the cost of the Buffalo Bills jersey.
Let y be the cost of the Miami Dolphin jersey.
According to the question, we have
9x+3y=899.40.......(1)
12x+2y=1139.30.....(2)
From (1),
[tex]\begin{gathered} 3y=899.40-9x \\ y=299.8-3x\ldots\ldots(3) \end{gathered}[/tex]Substitute equation (3) in equation (2), we get
[tex]\begin{gathered} 12x+2(299.8-3x)=1139.30 \\ 12x+599.6-6x=1139.30 \\ 6x=539.7 \\ x=89.95 \end{gathered}[/tex]Then the value of y is,
[tex]\begin{gathered} y=299.8-3(89.95) \\ y=29.95 \end{gathered}[/tex]Hence, the cost of the Buffalo Bills jersey is $89.95, and the cost of the Miami Dolphin jersey is $29.95.
