User talk:2A02:C7D:8428:6800:1A4:CA7A:B4E2:576

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

ANSWER EXPLANATION:Think of the equation as an equation for a line

Y=mx+b

where in this case

C= 5 9 (F−32)

or

C= 5 9 F− 5 9 (32)

You can see the slope of the graph is 5 9, which means that for an increase of 1 degree Fahrenheit, the increase is 5 9 of 1 degree Celsius.

C= 5 9 (F)

C= 5 9 (1)= 5 9

Therefore, statement I is true. This is the equivalent to saying that an increase of 1 degree Celsius is equal to an increase of 9 5 degrees Fahrenheit.

C= 5 9 (F)

1= 5 9 (F)

(F)= 9 5

Since 9 5 = 1.8, statement II is true.

The only answer that has both statement I and statement II as true is D, but if you have time and want to be absolutely thorough, you can also check to see if statement III (an increase of 5 9 degree Fahrenheit is equal to a temperature increase of 1 degree Celsius) is true:

C= 5 9 (F)

C= 5 9 ( 5 9 )

C= 25 81 (whichis≠1)

An increase of 5 9 degree Fahrenheit leads to an increase of 25 81, not 1 degree, Celsius, and so Statement III is not true.

The final answer is D. — Preceding unsigned comment added by 90.243.96.179 (talk) 16:46, 9 October 2018 (UTC)