At what temperature is centigrade equal to Fahrenheit?

Answer 1

The correct answer is of course -40 degrees.Whilst the equations are both linear, if you were to plot them both on the same graph, you would see that the results do intersect (at -40degrees).

Another, slightly more geeky, way to get the answer is to use the 2 equations

1. F=9/5C +32 ... used to convert from centigrade (Celsius) to Fahrenheit

2. C= 5/9(F- 32).... used to convert from Fahrenheit to Centigrade (Celsius)

Firstly write the write the equations so that they are equal (C=F), and then we can solve the simultaneous equations. So it looks like this:

9/5C+32 = 5/9(F-32). (this is when Fahrenheit and Celsius/ Centigrade are equal)

Then you solve for either F or C, by substituting for either F or C into the equation above (1. if you are solving for F, or 2. if you are solving for C) lets use number 1 and solve for F

It now looks like this:

9/5C+32 = 5/9((9/5C+32)-32) (I just put in (9/5C + 32), where F used to be.

To solve it we just use some simple rules of equations to try to get C on its own

Firstly divide both sides by 5/9) and it look like this:

9(9/5C+32)/5 = ((9/5C+32)-32)

Then simplify right hand side by removing the brackets like this:

9(9/5C+32)/5 = 9/5C [of course 32-32=0]

Next simplify the left hand side by opening brackets (it is done by multiplying everything inside the brackets by 9):

(81/5C+288)/5 = 9/5C

To get rid of 5 on bottom of left hand side, you muliply both sides by 5 and get:

(81/5C+288) = 45/5C

Next remove the brackets arent needed (nothing to do outside the brackets):

81/5C+288 = 45/5C

Next move Cs together and numbers to other side (by taking 288 from both sides and taking 45/5C from both sides), and it looks like this:

81/5C-45/5C =-288

Now solve the left hand side (easy as they are both over 5C), so its just 81-45:

36/5C=-288

Next multiply both sides by 5 (gets rid of the 5 on the bottom of left hand side) and you get:

36C=-1440

Now we divide both sides by 36 (makes C= to 1), and we get:

C=-1440/36

Now whack that into a calculator and Hey Presto:

C=-40

(it also work if you substitute for C)

So the temperature at which Celsius = Fahrenheit is -40 degrees

(I hope this helped)
Use this equation to convert degrees Celsius/Centigrade (ºC) to degrees Fahrenheit (ºF): [°F] = [°C] × 1.8 + 32

Answer 2

The formula conversion between Fahrenheit and Celsius is given below:

F = 9/5*C + 32

To find the temperature both scales are equal we can use another equation and combine it with this previous equation. The equation is simply F = C. Plug in for F or C and solve. Both cases are shown below:

C = 9/5*C + 32

C - 9/5*C = 32

-4/5*C = 32

C = (-32*5)/4 = -40

F = 9/5*F + 32

F - 9/5*F = 32

-4/5*F = 32

F = (-32*5)/4 = -40

Thus, at the cold temperature of negative 40, this temperature is the same on both the Fahrenheit and Celsius temperature scales.

Answer 3

Minus 40 degrees Celsius (centigrade) = Minus 40 degrees fahrenheit.

Answer 4

- 40 is the same in both Celsius and Fahrenheit scales.

Temperature Fahrenheit = Temperature Celsius(1.80) + 32

Answer 5

If you say, "It's forty degrees below zero," you don't have to specify whether you're using Fahrenheit or Celsius (Centigrade).

Answer 6

Tha happens to be at -40 degrees.

Answer 7

At -40 degrees.

Answer 8

At -40 degrees on both scales.

Answer 9

At -40

Answer 10

32o