C=5/9(F-32)


The equation above shows how temperature F, measured in degrees Fahrenheit, relates to a temperature C, measured in degrees Celsius. Based on the equation, which of the following must be true?

A temperature increase of 1 degree Fahrenheit is equivalent to a temperature increase of
5
9
degree Celsius.
A temperature increase of 1 degree Celsius is equivalent to a temperature increase of 1.8 degrees Fahrenheit.
A temperature increase of
5
9
degree Fahrenheit is equivalent to a temperature increase of 1 degree Celsius.
A) I only
B) II only
C) III only
D) I and II only

is it D

To determine which of the options must be true based on the given equation:

C = 5/9(F-32)

We can analyze the equation step by step:

1) To convert Fahrenheit to Celsius, we subtract 32 from the Fahrenheit temperature.
2) Then, we multiply the result by 5/9 to obtain the Celsius temperature.

Now let's analyze each option:

Option A: A temperature increase of 1 degree Fahrenheit is equivalent to a temperature increase of 5/9 degree Celsius.

To verify this, we need to determine the difference in Celsius temperature when the Fahrenheit temperature increases by 1 degree:

C2 = 5/9(F2-32)

For a temperature increase of 1 degree Fahrenheit:

C2 = 5/9((F+1)-32)
C2 = 5/9(F-31)

Comparing this to the original equation, we see that the Celsius temperature increases by 5/9 degree Celsius, indicating that option A is true.

Option B: A temperature increase of 1 degree Celsius is equivalent to a temperature increase of 1.8 degrees Fahrenheit.

To verify this, we need to determine the difference in Fahrenheit temperature when the Celsius temperature increases by 1 degree:

C2 = C+1
F2 = (9/5*C2)+32

Now, let's compare the Fahrenheit temperatures:

F2 = (9/5*(C+1))+32
F2 = (9/5*C)+(9/5)+32
F2 = (9/5*C)+57/5

From the original equation, we know that F = (9/5*C)+32. Comparing this to F2, we find that the difference in Fahrenheit temperature is not 1.8 degrees Fahrenheit but rather 57/5 degrees Fahrenheit, indicating that option B is false.

Option C: A temperature increase of 5/9 degree Fahrenheit is equivalent to a temperature increase of 1 degree Celsius.

To verify this, we need to determine the difference in Celsius temperature when the Fahrenheit temperature increases by 5/9 degree Fahrenheit:

C2 = 5/9(F+5/9-32)
C2 = 5/9(F-14/9)

Comparing this to the original equation, we see that the Celsius temperature increases by 5/9 degree Celsius, indicating that option C is true.

Based on our analysis, we can conclude that options A and C are true, while option B is false. Therefore, the correct answer is:

D) I and III only.