This is part of Wordless Wednesday…



Part of Wordless Wednesday…
The beautiful and talented Heather at Freebies4Mom.com sent me a post on An Easy Way to Convert Celsius to Fahrenheit.
It inspired me to draw the graphs of Celsius in terms of Fahrenheit and Fahrenheit in terms of Celsius.

Notice these two intersect at (-40, -40). Which means that -40°F is -40°C!
The x values on the red line are Celsius – so find the °C you have and then look at the y-value to convert to °F.
It’s just the opposite on the purple line.
Okay, fine. This isn’t the greatest way to convert – but it’s exciting to see it graphically. And it might be easier to convert this way for someone who’s more visual.
These two lines are inverses of each other. So the coordinates of one are switched to make the other.
Also, they mirror image across that 45° line. I marked the line with dashes and wrote on it.
And if you’re into this, their functional composition (both ways) is… x! (not factorial)
Take a look at the way J.D.Roth did it and then look at the graphs I have. Let your students find the way they like the best. And encourage them to create new ways!
Oh, yeah – and share what happens in the comments!



Part of Wordless Wednesday…

Thoughts? Share them in the comments. Also, tell your friends on twitter.


Part of Wordless Wednesday…

Ray’s Higher Arithmetic, original copyright 1880. Photo is of the 1908 printing, page 85.
enVisionMATH Grade 6, copyright 2009. Photo is of page 166.
Do you want to comment on this? How about tweet it out?


Part of Wordless Wednesday…

Image, cookies and decoration by my friend Amanda Farr.
Thanks, Amanda!


Part of Wordless Wednesday…

SISTER BERNARDINE teaches a class of mothers at St. Frances parochial school about the mysteries of the abacus.
The date is unknown, but by the looks of the outfits and the discoloring of the newspaper, I’d suspect it’s a while ago.


Part of Wordless Wednesday…

This is Wil Devine (@MathPsych), the Director of Research for MathFour.com, “doing research” with the Little Professor.
