The function is the formula to convert x °C to Fahrenheit units. Find

(i) F(0),


(ii) F(–10),


(iii) The value of x when f(x) = 212.


Interpret the result in each case.


Given: …(i)

To find: (i) F(0)


Substituting the value of x = 0 in eq. (i), we get




F(0) = 32


It means 0° C = 32° F


To find: (ii) F(-10)


Substituting the value of x = -10 in eq. (i), we get




F(-10) = 9 × (-2) + 32


F(-10) = -18 + 32


f(-10) = 14


It means -10° C = 14° F


To find: (iii) the value of x when F(x) = 212


It is given that


Substituting the value of F(x) = 212 in the above equation, we get






x = 20 × 5


x = 100


It means 212°F = 100°C


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