30,000 equals 30,000 ones, since you are basically counting by one.
Y - 4x = 7...y = 4x + 7
now sub 4x + 7 in for y in the other equation
2y + 4x = 2
2(4x + 7) + 4x = 2
8x + 14 + 4x = 2
12x = 2 - 14
12x = - 12
x = -1
y - 4x = 7
y - 4(-1) = 7
y + 4 = 7
y = 7 - 4
y = 3
solution is : (-1,3)
Answer:
The correct answer is (edit: b).
Step-by-step explanation:
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A.number of donuts delivered 2 hours from now.
2. Next=now +60+60
starting at 48 because 2 hours meant 2*60 = 60+60
B. number of donuts delivered 7 hours from now C
3.Next= now +420
starting at 48 because 7 hours meant 7*60 = 420 mn
C.number of donuts delivered n hours from now.
4. Next=now+60n
starting at 48 (this is obvious)
so finally,
D. number of donuts delivered 6 hours from now.
1. Next= now+ 6*60
starting at 48