X-12=20
x=20+12
x=32
answer is 32
4.5 feet = 54 in. 127 cm. = 50 in. 50 in.+54 in.=104 in.
If it takes m minutes to play on level, then in 60 minutes, the maximum number of levels you can play is 60 / m. Then, l <= 60/m.
If x is 1 which will be -1, y will be -1+5=4 (-1,4)
If x is 0, y will be 0+5=5