A look at solid figures form different perspectives

A look at solid figures form different perspectives Developed by Ivan Seneviratne

Let’s look at different views ü Look at a cone from a perspective view.

Look from different angles ü Check out the same figure from: The bottom The sides (or from any side view) The top

How to show side breaks ü Start with this special figure:

Check out the other views! Front left right back * note: the yellow lines indicates a break in the surface. top

Using Isometric dot paper ü sketch a rectangular solid 7 units long, 4 units wide, and 3 units high. 1. Draw the top of a solid 4 by 7 units. . . . . . . . . . .

2. Draw segments 3 units down from each vertex. (show hidden sides with dotted lines) . . . . . . . . . .

3. Connect the lower vertices. Shade the top of the figure for depth if desired. You have created a corner view of the solid figure. . . . . . . . . . .

Nets and Surface Area Imagine cutting a cardboard box along its edges and laying it out flat. The resulting figure is called a net. back = end top end front bottom A net is very helpful in finding the surface area of a solid figure.

Let’s look at another net ü This is a triangular pyramid. Notice that all sides lay out to be triangles. =

Find the surface area using a net 1. 2. 3. First, imagine the figure represented as a net. Find the area of each face. Find the sum of all the individual areas. 4 6 6 4 6 = 10 10 6 6 6 Surface area = (6 x 10) + ½(6)(4) + ½ (6)(4) = 60 + 12 = 204

This presentation is developed by Ivan Seneviratne © 2006 purely for personal use. ivanthexplorer@yahoo. co. uk