practice naming solids based on demonstration, GT, and reading pp 505-507
discover and apply formulas for pyramids and cones (V=1/3 BH) where b is area of base, H is height of solid.
cross-sections of solids demonstration - what two dimensional figure do you see when you slice a solid with a plane.
A grade was taken on HW 11 and the assignment was shared, debugged and corrected during class.
Solids were named with all possible names from images on the screen.
A demonstration by students with black beans filling up a cone and transferring to a cylinder showed that the volume of a cone is 1/3 the volume of the cylinder with same radius and height.
We practiced 3-4 problems with pyramids and cones.
Then Ms. Bogart demonstrated what we mean by cross-sections of solids. Solid models were used, some of which had easy to see cross-sections. There is no homework over this yet.
HW #12 is p 518: 9,15 and p 425: 1-9,14. On all volume problems, write out the correct formula, show the values substituted for the variables, and then you may use the calculator to get "the answer". Try some mental math skills if you can.
We will have a Trig Quiz for 24 pts on Tues-Wed next week. The Unit Quiz - 50 pts - over volume and related topics is May 15-16.
No attachments today.
If you were absent today, you might want to Google a short video or images of cross sections of geometric solids.