The surface of Grand Lake is at an elevation of 648 ft. During the current drought, the water level is dropping at a rate of 3 inches per day. If this trend continues write an equation that gives the elevation in feet of the surface of Grand Lake after x days.

Given situation:

=> A grand lake surface is equals to 648 feet

=> Every day the water drops 3 inches

Now, we need ti create an equation that shows the process of given situation in how many days.

=> Since we have 2 different unit of measure, we need to convert feet to inches

=> 1 foot is equals to 12 inches

=> 648 feet x 12 inches = 7776 inches

Now, we have the same unit of measure

Let’s start the equation:

=> 7776 inches - 3inches (x) where x is the number of days.