Answer:
Yes, x-10 is an accurate expression. . . .
Hope that helps
X = 250 mg tabs
y = 500 mg tabs
2200x + 1800y = 39200....multiply by -1
2200x + 2200y = 44000
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-2200x - 1800y = - 39200 (result of multiplying by -1)
2200x + 2200y = 44000
--------------------------------add
400y = 4800
y = 4800/400
y = 12...... the 500 mg tabs (y) costs $ 12 per bottle
2200x + 2200y = 44000
2200x + 2200(12) = 44000
2200x + 26400 = 44000
2200x = 44000 - 26400
2200x = 17600
x = 17600/2200
x = 8 <== the 250 mg tabs (x) costs $ 8 per bottle
D is the correct answer.
We do not need math in this instance, just knowledge.
We know that the answer will point to 0, not infinity. There are constraints. Also note that 1.75*7=12.25, which means you can fit no more than 7 books in the bag.
What best describes this? Answer Choice D