Students understand that a scale drawing is either the reduction or the enlargement of a two-dimensional picture.
Students compare the scale drawing picture with the original picture and determine if the scale drawing is a reduction or an enlargement.
Students match points and figures in one picture with points and figures in the other picture.
Intro Activity: Can You Guess the Image?Example 1
Scale Drawing: a reduced or enlarged two-dimensional drawing of an original two-dimensional drawing.
Derek’s family took a day trip to a modern public garden. Derek looked at his map of the park that was a reduction of the map located at the garden entrance. The dots represent the placement of rare plants. The diagram below is the top-view as Derek held his map while looking at the posted map.
What are the corresponding points of the scale drawings of the maps?
Cleleste drew the outline of a building for a diagram she was making and then drew a second one mimicking her original drawing. State the coordinates of the vertices and fill in the table.
Scale Drawing: A drawing in which all lengths between points or figures in the drawing are reduced or enlarged proportional to the lengths in the actual picture. A constant of proportionality exists between corresponding lengths of the two images.
Reduction: The lengths in the scale drawing are smaller than those in the actual object or picture.
Enlargement/Magnification: The lengths in the scale drawing are larger than those in the actual object or picture.
One-to-one Correspondence: Each point in one figure corresponds to one and only one point in the second figure.