CREATE TABLE table_42082 ("Team" TEXT, "Tries for" FLOAT, "Tries against" FLOAT, "Try diff" TEXT, "Points for" FLOAT, "Points against" FLOAT, "Points diff" TEXT)

How many Tries against has a Try diff of 17 and Points for smaller than 80?
SELECT COUNT("Tries against") FROM table_42082 WHERE "Try diff" = '–17' AND "Points for" < '80'
SELECT COUNT("Tries against") FROM "table_42082" WHERE "Points for" < '80' AND "Try diff" = '–17'