I passed back last Friday's assessments. Nearly every student struggled on Skill 13, solving for y and eliminating fractions before solving an equation. We went over it as a class so that they could study it before the assessment this Friday:
Here's an example of the classwork. Megan was able to show her table for the bunny and the cat. Also, her graph shows the point of intersection with the coordinates labeled.
Students will continue with the same lesson with bigger numbers of writing an equation and using the equal values method.
What questions do you have, what information do you need to answer it?
Once you've shared your ideas, and requested information, here is Act Two:
After student's share their solution strategies, let's see the answer, Act three:
Extension: How long would it take a 26 centimeter tall candle to burn out with same width?
After Act one, students told me what information they need and I told them I wanted a neatly labeled scatterplot, line of best fit, equation of it, and the slope and y-intercept interpreted. As you can see, I like 2 different answers students came up with for the slope. -1/20 meant that it shrinks 1/20 of a centimeter each minute or that it shrinks 1 whole centimeter every 20 minutes. That was a great interpretation of the rise and run of slope.
Here you can see that Davin wrote his equation and substituted zero for y and solved for x. He got 340 minutes. The answer ended up being a little more than that. I believe this activity an lead into a discussion about residuals tomorrow.
This is some work from yesterday's Hot Dog eating lesson that Alex D finished that tracked Kobayashi and Black Widows total hot dogs eaten after certain rounds. You can see his parabolic sequence equations at n squared and n squared plus n.