Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE table_21879 ( "Position" real, "Team" text, "Played" real, "Won" real, "Drawn" real, "Lost" real, "Goals For" real, "Goals Against" real, "Goal Difference" text, "Points 1" text )

### Question ###
When +10 is the goal difference what is the goals for?

### Accurate SQL ###

SELECT "Goals For" FROM table_21879 WHERE "Goal Difference" = '+10'