Question

The water level in Lake Travis currently is 325 ft. deep. If the water decreases at an average rate of -2.1 feet per year, what will be Lake Travis’s water level after 8 years?

Answer 1

308.2 ft

Explanation:

To solve we can first make an equation. y is the total water level after x amount of years.

y = -2.1x + 325

325 is the y intercept cause the water level is 325ft deep after 0 years.

-2.1 is the slope because the water level decreases by 2.1 ft every year.

To find the water level after 8 years, we plug in 8 for x and solve,

y = -2.1(8) + 325

y = -16.8 + 325

y = 308.2 ft