The expression is .
First locate 13 then move 7 units to left on number line.
The final position is
The value of expression is .
![\"\"](\"/userfiles/image/steps_images/step1.JPG\")
![\"\"](\"/test/fckeditor/editor/plugins/fckeditor_wiris/integration/showimage.php?formula=e7616625d5fb3ac1e9826822c1e118fb.png\")
. ![\"nimber](\"/userfiles/image/Library/Algebra1/nimber_line_diagram_13+7.gif\")
![\"\"](\"/test/fckeditor/editor/plugins/fckeditor_wiris/integration/showimage.php?formula=27742ffbb932cdcad83d0e40843478dc.png\")
![\"\"](\"/userfiles/image/steps_images/solution.JPG\")
![\"\"](\"http://www.mathskey.com/test/fckeditor/editor/plugins/fckeditor_wiris/integration/showimage.php?formula=27742ffbb932cdcad83d0e40843478dc.png\")
.