A temperature of 0 degrees C equals 32 degrees F and 25C equals 77F use this equation to find the fahrenheit temperature for 40C

Question

anonymous · Answer

F=9C/5+32 I think

anonymous · Answer

To answer this, they're assuming you'll assume the relationship between the temperatures is linear.  You want Fahrenheit to be the 'y' and Celsius to be the 'x'.  You know the following:

when x = 0, y = 32  ---> (x_1, y_1)
when x = 25, y = 77  ---> (x_2, y_2)

You may now use the two-point formula for a straight line:
$$y-y_1=\frac{y_2-y_1}{x_2-x_1}(x-x_1) \rightarrow y-32=\frac{77-32}{25-0}(x-0)$$
that is,$$y-32=\frac{45}{25}x \iff y=\frac{9}{5}x+32$$

anonymous · Answer

When the temperature is 40 degrees C, x=40, and so the temp. in F is,$$y=\frac{9}{5}40+32=104 ^oF$$

anonymous · Answer

Yeah, Rouault, you were right ;)

anonymous · Answer

:) I googled it before you answered to see