Answer:
w = 4
Step-by-step explanation:
you would do this by re-arranging the equation
6 = 5w-10-w (move w to the other side)
6 = 4w-10 (because 5w-w = 4w)
6+10=4w (move 10 to the other side)
16 = 4w (add 6 and 10)
4 = w (divide both sides by 4)
324 gallons, 3 fish a day
54 x 6
24/8
30.4
if you want the basic perimeter just add up all the sides