PLS HELP
heres my question i pinned as a picture

Advanced ($10): A
Door ($13): D
Money: 10A + 13D = 544 ⇒ 1(10A + 13D = 544) ⇒ 10A + 13D = 544
Quantity: A + D = 46 ⇒ -10(A + D = 46) ⇒ -10A - 10D = -460
3D = 84
D = 28
Quantity: A + D = 46 ⇒ A + (28) = 46 ⇒ A = 18
Answer: advanced = 18 people, at the door = 28 people