"Kristin sold 9 packages of chocolate chip and 14 packages of dough for $246", this can be expressed as
[tex]9x+14y=246[/tex]Where x is chocolate chips and y is cookie dough.
"James sold 12 packages of chocolate chip and 7 packages of dough for $153".
[tex]12x+7y=153[/tex]Let's multiply the second equation by -2.
[tex]\begin{gathered} 9x+14y=246 \\ -24x-14y=-306 \end{gathered}[/tex]Then, we combine the equations
[tex]\begin{gathered} -15x=-60 \\ x=-\frac{60}{-15} \\ x=4 \end{gathered}[/tex]