The average temperature for four days was 22 degrees what must be the temperature be on the fifth day in order to make the average temperature for the five days

Find the value of x that will make l ll m

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In order for the function to be linear, what must m be and why? m = 22 because the rate of change is 1. m = 20 because the rate of change is 3. m = 22 because the rate of change is -1. m = 20 because the rate of change is -3.