Addition & subtraction strategies to solve two-digit equations using an open number line.

Addition and subtraction with regrouping using different strategies to solve.

If you want to show line numbers in a Google Docs document, then you can do it using the Line Numbers for Google Docs Chrome extension.

After adding support for non-printing characters earlier this year, Google Docs is rolling out line numbers. Commonplace in legal documents, Google Docs will automatically calculate and show ...