Answer:
[tex]\mathrm{A.\:}\begin{cases}3x+2y=170,\\4x+6y=360\end{cases}\\\\\mathrm{B.\:} \$ 30[/tex]
Step-by-step explanation:
We can write the following system of equations:
[tex]\begin{cases}3x+2y=170,\\4x+6y=360\end{cases}[/tex], with variables as defined in the question.
Multiply the first equation by [tex]-3[/tex] and add both equations to isolate and solve for [tex]x[/tex]:
[tex]\begin{cases}-9x-6y=-510,\\4x+6y=360\end{cases}\\-5x=-150,\\x=\fbox{$\$ 30$}[/tex].