the answer is the last one
Answer:
The first submarine needs to travel at a rate of [-180 – (-1,320)] ÷ 60 = 19 feet per minute.
The second submarine needs to travel at a rate of [-180 – (-1,440)] ÷ 60 = 21 feet per minute.
21 – 19 = 2, so the second submarine must travel 2 feet per minute faster than the first sub.
we have
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Step 1
Eliminate the parenthesis
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Step 2
Group terms that contain the same variable
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Step 3
Combine like terms
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therefore
the answer is
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A because all of the variables stay constant
To find x, refer to the attachment