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=□
Determine Initial Thickness: To find the equation that represents the relationship between the ice sheet's thickness (y) and the number of weeks (x), we need to determine the starting thickness of the ice before it began to melt. We know that the ice thickness decreases by 0.2 meters per week, and after 7 weeks, it is 2.4 meters thick.
Calculate Total Decrease: We can calculate the initial thickness by adding the total decrease in thickness over 7 weeks to the final thickness. The total decrease is 7 weeks times 0.2 meters per week.Total decrease = 7 weeks ×0.2 meters/week = 1.4 meters.
Find Initial Thickness: Now, we add the total decrease to the final thickness to find the initial thickness.Initial thickness = Final thickness + Total decrease = 2.4 meters + 1.4 meters = 3.8 meters.
Write Equation: With the initial thickness found, we can write the equation that represents the relationship between the thickness y and the number of weeks x. Since the thickness decreases by 0.2 meters each week, the equation is:y=Initial thickness−(Rate of decrease×Number of weeks)y=3.8 meters−0.2 meters/week×x
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