To find the rows which exist in all 5 tables use the INNER JOIN syntax to join them all together.
JOIN t2 on t1.id = t2.id
JOIN t3 on t1.id = t3.id
JOIN t4 on t1.id = t4.id
JOIN t5 on t1.id = t5.id</pre>
To see which rows exist in two of the tables only join those two tables together.