CREATE TABLE table_17709 ("Club" TEXT, "Overall Record" TEXT, "Goals For" FLOAT, "Goals For Avg." TEXT, "Goals Against" FLOAT, "Goals Against Avg." TEXT)

The Dallas Burn had a 12-9-7 record and what number of goals for?
SELECT "Goals For" FROM table_17709 WHERE "Overall Record" = '12-9-7'
SELECT "Goals For" FROM "table_17709" WHERE "Overall Record" = '12-9-7'