A lake near the Arctic Circle is covered by a thick sheet of ice during the cold winter months. When spring arrives, the warm air gradually melts the ice, causing its thickness to decrease at a rate of 0.2 meters per week. After 7 weeks, the sheet is only 2.4 meters thick.Let y represent the ice sheet's thickness (in meters) after x weeks.Complete the equation for the relationship between the thickness and number of weeks.y=□
Q. A lake near the Arctic Circle is covered by a thick sheet of ice during the cold winter months. When spring arrives, the warm air gradually melts the ice, causing its thickness to decrease at a rate of 0.2 meters per week. After 7 weeks, the sheet is only 2.4 meters thick.Let y represent the ice sheet's thickness (in meters) after x weeks.Complete the equation for the relationship between the thickness and number of weeks.y=□
Find Initial Thickness: To find the initial thickness of the ice sheet before it started melting, we need to work backwards from the given information. We know that after 7 weeks, the ice is 2.4 meters thick and it decreases by 0.2 meters each week. So, we can calculate the initial thickness by adding 7 weeks' worth of melting to the final thickness.Initial thickness = 2.4 meters + (7 weeks ×0.2 meters/week)
Calculate Initial Thickness: Performing the calculation for the initial thickness:Initial thickness = 2.4 meters + (7×0.2 meters)Initial thickness = 2.4 meters + 1.4 metersInitial thickness = 3.8 meters
Write Equation Model: Now that we have the initial thickness, we can write the equation that models the relationship between the thickness of the ice sheet y and the number of weeks x. Since the ice is melting at a constant rate, the equation will be linear, in the form y=mx+b, where m is the rate of change and b is the initial value.In this case, m is −0.2 (since the ice is decreasing by 0.2 meters each week), and b is the initial thickness, which we found to be 3.8 meters.So the equation is y=−0.2x+3.8.
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