Join condition syntax for comparing a sequence of digits

I have two tables, one of which has a 2 digit customerId integer column and another one that has a transactionId integer column. The second and third digits of the transactionId column correspond to customerIds. I would like to perform a join on the two tables with by 'matching' the transactionId and customerId as the join condition. Something like

customerId LIKE '_transactionId%

Is this possible?