Question

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 0.20 meters per week. After 7 weeks, the sheet is only 2.42 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.

Answer 1

Explanation:

We know that the thickness of the lake decreases at a rate of 0.2 meters per week, so we can write:

S(t)=-0.2t+4

we also know that after 7 weeks, the sheet is only 2.42 meters thick, which means we can write:

S(7)=2.42

S(7)=-0.2*7+X

S(7)=-1.4+X

2.42=-1.4+X

X=3.82

So, the function is: S(t)=--0.2*t+3.82

Answer 2

y = 3.8 - 0.2x

Explanation:

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