Answer: The break even point is when they have sold 16 books and have made $288
Step-by-step explanation: The costs are modeled in the equation y = 12x + 96. x is the number of books sold.
The earnings are modeled by he equation y = 18x.
Substitute 18x for y and solve for x.
18x = 12x + 96 Subtract 12x from both sides.
6x = 96 Divide both sides by 6
x = 16
Substitute into the original equations to solve for y
y = 12(16) + 96
y = 192 + 96
Y = 288
y = 18(16)
y = 288