Question

The local river is 19 feet deep in most places. Drought has impacted the area for the last few weeks. The river declined 1/7 foot per day over this time period. This can be modeled by the equation y=- 1/7 x+19. Use this model to predict the depth of the river after 4 weeks, or 28 days of drought.

Answer 1

To predict the river depth after 4 weeks of drought, substitute x=28 (days) into the model y=-1/7x+19, yielding a predicted river depth of 15 feet.

Step-by-step explanation:

The question asks to predict the depth of a river after 4 weeks of drought using the given linear model y = -1/7x + 19, where 'x' is the number of days and 'y' is the depth in feet.

First, we need to convert weeks into days to use the model properly. We know that 4 weeks equals 28 days (since 1 week is 7 days).

Next, we substitute 'x' with 28 days in the model:

y = -1/7(28) + 19

y = -4 + 19

y = 15 feet

Therefore, after 4 weeks or 28 days of drought, the predicted depth of the river is 15 feet.