How come everytime a Friday lands on the 13th day of the month, is it considered bad luck?

this day is considered to be inauspisious because on a friday, jesus was crusified. and 13th teh number is said to be unlucky beacuse a year has only 12 months and there were only 13 people in Jesus's Last Supper on the day he was crusified. apart from this in America, many accidents are reported and not many people drive at this day.