We were given an assignment to find a formula for finding the density of water. I wasn't in class when the assignment was given, but the teacher gave the class two values:
density H2O at 20 degrees C= .998823 g/mL
density H2O at 25 degrees C= .99707 g/mL
A friend of mine told me that the class was told to find the slope of this, when x= density and y= temperature. Then, we were to take this function, which is linear, and put it into y= mx + b form.
I know that the calculation for slope is
m= (y2-y1)/(x2-x1)
So, if my points were:
Pt1= 20.0, .998823
Pt2= 25.0, .99707
then my slope would be
-.00175/5.00 or -3.50 E-4
Is it possible to have a negative slope?
I know this equals m, so my equation right now would look like this:
y= -3.50E-4(x) + b
How do I find b??
Look at the two points. As T goes up, density goes down. That will give you the negative slope. To find b, set x = 0
That won't work, will it? If you are graphing the line, b is the y intercept.