The temperature of a chemical solution is originally 21^\circ\text{C}21 ∘ C21, degrees, start text, C, end text. A chemist heats the solution at a constant rate, and the temperature of the solution is 75^\circ\text{C}75 ∘ C75, degrees, start text, C, end text after 121212 minutes of heating. The temperature, TTT, of the solution in ^\circ\text{C} ∘ Cdegrees, start text, C, end text is a function of xxx, the heating time in minutes. Write the function's formula. T=

T(x) = 21 + 4.5x

Step-by-step explanation:

Given :

Original temperature = 21°C

Final temperature = 75°C

Time, x = 12 minutes

The temperature, T as a function of x, heating time in minutes :

We need to obtain the constant heating rate per minute :

Final temperature = initial temperature + (constant rate change,△t * time)

75 = 21 + 12△t

75 - 21 = 12 △t

54 = 12 △t

△t = 54 / 12

△t = 4.5°C

Hence, temperature change is 4.5°C per minute.

Hence,

T(x) = 21 + 4.5x

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