Question

When temperature is zero degree Celsius, the Fahrenheit temperature is 32. When the Celsius temperature is 100, the corresponding Fahrenheit temperature is 212. Express the Fahrenheit temperature as a linear function of C, the Celsius temperature, F(c).

Answer 1

Answer:

$\\ y = 1.8(x) + 32$ or $\\ y = \frac{9}{5}(x) + 32$

or equivalently:

$\\ F = 1.8(C) + 32$ or $\\ F = \frac{9}{5}(C) + 32$

Step-by-step explanation:

To express the Fahrenheit temperature as a linear function of the Celsius temperature, F(c), we can proceed as follows.

We can use here the two-point form equation of a line:

$\\ y-y_1 = \frac{y_2 - y_1}{x_2 - x_1}(x-x_1)$ [1]

We are asked to express the Fahrenheit temperature as a function of Celsius temperature, so the independent variable, in this case, is x (Celsius temperature) and the dependent variable is y (Fahrenheit temperature).

When temperature is zero degree Celsius ($\\x_1 = 0$), the Fahrenheit temperature is 32 ($\\y_1 = 32$).

When the Celsius temperature is 100 ($\\x_2 = 100$), the corresponding Fahrenheit temperature is 212 ($\\y_2 = 212$).

Then, using [1], we have:

$\\ y-32 = \frac{212 - 32}{100 - 0}(x-0)$

$\\ y-32 = \frac{180}{100}(x)$

$\\ y-32 = 1.8(x)$.

It could be also be written as:

$\\ y-32 = \frac{18}{10}(x)$ = $\\ y-32 = \frac{9}{5}(x)$, as it commonly appears in books.

Then the Fahrenheit temperature express as a linear function of the Celsius temperature, F(c) is ( solving the equation for y ) :

$\\ y = 1.8(x) + 32$ or $\\ y = \frac{9}{5}(x) + 32$.

Or equivalently:

$\\ F = 1.8(C) + 32$ or $\\ F = \frac{9}{5}(C) + 32$

We can check this using the given values from the question:

For 0 Celsius degrees, the Fahrenheit temperature is:

$\\ y = 1.8(0) + 32$ = 32 Fahrenheit degrees.

For 100 Celsius degrees, the Fahrenheit temperature is:

$\\ y = 1.8(100) + 32 = 180 + 32$ = 212 Fahrenheit degrees.