a) 33=6x (x being the amount of money you spend per hour) 
You divide both sides by 6 to get x alone. 
33/6 = 5.5 
$5.5 dollars per hour
b) 7=51x (x being the number of acres that can be planted per pound of seeds)
You divide both sides by 51 to get x alone.
7/51 (there is no way to simplify this further)
7/51 acres per pound