The geoboard shows a scale drawing of a banner shape. Treat the lower-left vertex of the shown polygon as \((0,0)\). One peg spacing is \(1\) unit, positive x is to the right, and positive y is upward.
A second drawing must reproduce the same shape at a scale factor of \(2\), with its corresponding lower-left vertex also at \((0,0)\).
a) Starting at the lower-left vertex and moving counterclockwise, list the coordinates of the vertices in the shown drawing.
b) List the coordinates of the corresponding vertices in the second drawing.
c) Explain how the scale factor changes every side length.

Hints
- Use peg spacings, not physical measurements of the displayed image.
- Record each vertex relative to the stated lower-left origin before changing the scale.
- A scale factor changes coordinate displacements from the origin by the same multiplicative factor.
Solution
1. Counting peg spacings from the lower-left vertex, the shown vertices are \((0,0)\), \((3,0)\), \((3,2)\), \((1,3)\), and \((0,2)\).
2. A scale factor of \(2\) doubles each coordinate measured from the common origin.
3. The second drawing therefore has vertices \((0,0)\), \((6,0)\), \((6,4)\), \((2,6)\), and \((0,4)\).
4. Because every coordinate displacement is doubled, every side length is doubled and the shape is reproduced at the required scale.
Answer
a) \((0,0)\), \((3,0)\), \((3,2)\), \((1,3)\), \((0,2)\)
b) \((0,0)\), \((6,0)\), \((6,4)\), \((2,6)\), \((0,4)\)
c) Every side length is multiplied by \(2\).