Question

7. The relationship between the latitude Lof a city in the Northern Hemisphere and its average annual temperature Tis modeled by the function T = -0.68L + 89.5. The slope of this linear function means (A) That temperature at the equator would be 89.5°. (B) For every degree increase in latitude, the average annual temperature increases by 89.5º. (C) For every degree increase in latitude, the average annual temperature increases by 0.68 (D) For every degree increase in latitude the average annual temperature decreases by 0.68º.

Answer 1

We are given the following function that models the temperature T as a function of the latitude L:

T = - 0.68 L + 89.5

We see that the temperature is in fact a linear function of slope -0.68 degrees/latitude.

Since the latitude of the Equator is 0 degrees, then, the equation tells us that the temperature at the Equator is:

T = - 0.68 (0) + 89.5 = 89.5 degrees of annual temperature. But this is NOT related to the slope.

The other two statements (B and C) are not correct,

The last statement D is correct, since for every degree increase in latitude, there is an annual decrease of temperature by 0.68 degrees, and this is what the slope expresses.

Please select answer D.