why isn't minimum wage enough? [NOW WITH THE MATH TO BACK IT UP!]

So many people have always tried to say you can't live of minimum wage. But who has ever TRULY done the math? Now i can say that i have. This is done for people on ssi at the max amount allowed. It should be noted that the max allowed a month before you lose ALL your benefits is 1130.00 a month,
Cite for reference here: http://www.nolo.com/
So here goes:

1130.00 (1129.00) a month before losing money.
733.00 max ssi
Able to work Monday through Friday
200 a month to cover food.

5.43 an hour minimum wage (after taxes)
396.00 maximum allowed income
99.00 a week
19.80 a day
3 hours 40 minutes a day (7.25 an hour, minus taxes  [1.81])
18 hours 20 minutes a week (3 hours times five days, 40 minutes times 5 [200 minutes. 200 divided by 60 equals 3.33, or 3 hours 20 minutes])
Mortgage 520.00
Total max allowed 609 (Max safe amount 213.00, Max allowed before deductions 396.00)
152.25 a week
30.45 a day
5 hours 36 minutes a day (7.25 an hour, minus taxes  [1.81])
28 hours a week (5 hours times five days [25], 36 minutes times 5 [180 minutes. 180 divided by 60 equals 3 hours])

396.00 maximum allowed income
99.00 a week
19.80 a day
2 hours 15 minutes a day (7.25 an hour)
11 hours 15 minutes a week (2 hours times five days [10], 15 minutes times 5 [75 minutes, or 1 hour 15 minutes])
Mortgage 520.00
Total max allowed 609 (Max safe amount 213.00, Max allowed before deductions 396.00)
152.25 a week
30.45 a day
4 hours 12 minutes a day (7.25 an hour)
21 hours a week (4 hours times five days [20], 12 minutes times 5 [60 minutes]

After taxes max income allowed (5.43 am hour):
Minimum of 18 hours 20 minutes a week,  (before i start to lose ssi)
Maximum of 28 hours a week. (Before i lose the money for the mortgage)

Before taxes max income allowed (7.25 an hour):
Minimum of 11 hours 15 minutes a week (before i start to lose ssi)
Maximum of 21 hours a week. (Before i lose the money for the mortgage)

Now let's calculate for minimum wage in its entirety:
Before taxes:
1130 a month
282.50 a week
56.50 a day
7 hours 48 minutes a day (56.50/7.25 [an hour]=7.8 hours [8=4/5=12x4=48])
10:00 am to 6 pm
39 hours a week

After taxes:
1130 a month
282.50 a week
56.50 a day
10 hours 24 minutes a day (56.50/5.24 [an hour]=10.40 hours [4=2/5=12×2=24])
52 hours a week

So IT'S IMPOSSIBLE.