Background[br]These two shapes are going to be reflected over two lines rather than just one.  Again, [i]GeoGebra[/i] will do this reflecting for you.[br][br][b]Step 1.  Construct Reflections [/b][br]Using the MOVE [icon]/images/ggb/toolbar/mode_move.png[/icon] tool, click on the check-box to turn on the lines for reflection. [br]Select the REFLECT OBJECT ABOUT LINE tool [icon]/images/ggb/toolbar/mode_mirroratline.png[/icon].[br]To use this tool, first click on the red shape then click on the dashed black Line Segment AB. [br][br]Now, one at a time, reflect both of the shapes about the Line Segment CD. [br][br]Using the MOVE tool [icon]https://www.geogebra.org/images/ggb/toolbar/mode_move.png[/icon], click the check-box to turn off the dashed black line segments. [br][br]Now you can see your new red shape created by reflecting the original red shape about two lines of symmetry.[br][br][b]Step 2.  Repeat on a New Shape[/b][br]Repeat this same process for the blue shape.[br][br][b]Step 3.  Observe the New Shapes[/b][br]Using the MOVE tool [icon]https://www.geogebra.org/images/ggb/toolbar/mode_move.png[/icon], click on the check-box again to turn on the dashed line segments again. [br][br]Each of these line segments is a [b][i]line of symmetry[/i][/b].  Shapes can have more than one line of symmetry.