Finding Surface Area

Math 6

Objectives

1- Represent three-dimensional figures using nets made up of rectangles and triangles, and use the nets to find the surface area of these figures.

2- Apply these techniques in the context of solving real-world and mathematical problems.

Regular Polygons

Geometric Shapes

Polygons

1. Plane (flat) closed figures.

2. Sides are line segments.

Polyhedra (Polyhedrons)

1. solid figures(3-dimensional)

2. Sides are called faces.

3. Edges are line segments

Solid (3-Dimensional) Geometric Shapes

Cube

A net is a two-dimensional representation of a three-dimensional

figure.

How to Find Surface Area

1. Find the area of each face.

2. Add them all together.

Notice that parallel lines on a net are congruent.

Nets of triangular prism

Nets of pyramids

Nets of pyramids

We can describe nets and their solids by the number of:

edges

vertices

faces.

Solids include rectangular and triangular prisms

Edges Vertices Faces

Rectangular Prism

Triangular Prism

Here is a website which might be helpful.

http://illuminations.nctm.org/ActivityDetail.aspx?ID=205

Keys to Geometry

Master the vocabulary1. Polygon

2. Parallel

3. Perimeter

4. Perpendicular

5. Area

6. Rectangle

7. Right angle

8. Line segments

Keys to Geometry

Master the vocabulary1. Polygon

2. Trapezoid

3. rhombus

4. parallelogram

5. Complex figure

6. Regular polygon

Online Math Dictionaries

http://www.mathsisfun.com/definitions/letter-a.html

http://www.icoachmath.com/math_dictionary/mathdictionarymain.html#P

http://my.hrw.com/math06_07/nsmedia/tools/glossary/msm/glossary.html

Guided Practice 1

The figure is a cube.

Find the surface area.

The figure is a triangular prism.

Find the surface area.

Guided Practice 2

The figure is a pyramid with a square base.

Find the surface area.

Guided Practice 3

The figure is a pyramid with a triangular base. Find the surface area.

Guided Practice 4

Conclusion1. Surface Area of a solid means the

amount of space on the surface.

2. It is a measure of area, thus the units are square units.

3. We can find surface area of prisms and pyramids by finding the area of each face and adding.

4. A net can be helpful to use.

AssignmentFind the surface area of solids.

1. Solve the practice exercises on the attached page. Show all work.

"No employment can be managed without

arithmetic, no mechanical invention without geometry." ~Benjamin Franklin