Incorrect. The system that models this situation is $\displaystyle{d}+{c}\le{10}\usepackage{cmbright}\Huge\$ and $\displaystyle{20}{d}+{12}{c}\le{120}\usepackage{cmbright}\Huge\$ . Draw solid boundary lines in the first quadrant. Use test points to determine which side of each to shade. Starting at 4 on the d-axis, move up through the region. Find the highest point for which c is a whole number. That value of c is the greatest number of CDs that Chase can buy.