Answer :
x is amount of books.
x ≤ 9 if the books are 2 inches thick.
x ≤ 18 if the books are 1 inches thick.
Equation for 1 inches.
x ≤ 18
Equation for 2 inches.
2x ≤ 18
Equation for both.
x + 2y = 18
y is amount of 2 inch books
This one equation above is standard form.
x ≤ 9 if the books are 2 inches thick.
x ≤ 18 if the books are 1 inches thick.
Equation for 1 inches.
x ≤ 18
Equation for 2 inches.
2x ≤ 18
Equation for both.
x + 2y = 18
y is amount of 2 inch books
This one equation above is standard form.