Suppose a submarine is 480 feet below sea level. The submarine rises 40 feet per minute. Write an integer to express the time it takes to reach the surface.

12 minutes.

Step-by-step explanation:

Let x represent number of minutes.

We have been given that the submarine rises 40 feet per minute. So rise in elevation of submarine in x minutes would be .

We are also told that the submarine is 480 feet below sea level. This means that initial position on y-intercept is .

Submarine's final elevation after x minutes would be .

The submarine will reach on the surface, when final elevation of submarine is equal to 0.

Therefore, it will take 12 minutes for the submarine to reach the surface.

2x^2+5x+17

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