Thread: changing celsius to F

45.7°f = what in celsius

Is this the equation I should be using

C = °F-32/1.8
C= 45.7-32/1.8= 7.6

check it yourself ...

Fahrenheit to Celsius Converter

Originally Posted by Louisana1

Is this the equation I should be using

C = °F-32/1.8
C= 45.7-32/1.8= 7.6

The equation is wrong as written, though the answer 7.6 is (approximately) correct.

Your answer is correct but the correct equation for Fahrenheit to Celsius is :
(F - 32) x 5/9 = C
where F=45.7
Thus,
(45.7-32)*5/9=7.6

Composition of Functions

To derive the formula, use the freezing and boiling points of water, to get the slope of the line:



Now, use the point-slope formula:

Originally Posted by Louisana1

45.7°f = what in celsius

Is this the equation I should be using

C = °F-32/1.8
C= 45.7-32/1.8= 7.6

You mean C= (F- 32)/1.8. What you wrote really means C= F- (32/1.8)
You can check that is correct by checking the "easy values". The freezing point of water is 0 C and 32F:
(32-32)/1.8= 0/1.8= 0 so that is correct.
The boiling point of water is 100 C and 212 F:
(212- 32)/1.8= 180/1.8= 100 so that is correct.

Since this is a "linear" equation and two points determine a line you know that is the correct formula for any F.