Page 5 - Equations, substitution formulae

Formulae
The formula used to change temperature in Fahrenheit, ºF to degrees Celsius, ºC is as follows:

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C = ( − 32)
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where ºC represent temperatures in degrees Celsius and ºF, temperatures in Fahrenheit.

a. Change the following temperatures to Degrees Celsius, ºC i. 105ºF ii. 35 ºF

b. Change the following temperatures to Fahrenheit, ºF i. 10 ºC ii. 33 ºC

Solution

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a. i. C = ( − 32). ii. C = ( − 32).
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C = ( 105 − 32). C = ( 35 − 32).
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C = × 70 C = × 3
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105º = 38,89 º 35 º = 1,67 º

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b. i. C = ( − 32). ii. C = ( − 32).
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10 = ( − 32). 33 = ( − 32).
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9 5 9 9 5 9
10 × = ( – 32)× × 33 = ( − 32) ×
5 9 5 5 9 5

18 = − 32 59,4 = − 32
18 + 32 = 59,4 + 32 =
50 = 91,4 =
∴ 10 º = 50 ºF ∴ 33 º = 91,4 ºF