I need to write a macro that will do the following

If there is a check-mark symbol in a given cell on a row of data, all cells
preceeding the check-mark cell will be grayed out.

If the check-mark symbol is problematic, I can possibly pursuade my coworker
to enter a certain alphanumeric character in the cell instead.

For example:

Row 9, column H has the checkmark or other "flag"
Column a - g would be grayed out on that line only when the macro is run