The words "spent less than $26" can be symbolized as <$26
Nachos are $8
Quesadillas are $5
If n = number of nachos bought and q the number of quesadillas, you can calculate what he spent as:
8n+5q
Since he bought less that 26 dollars in nachos and quesadillas, you make the inequality:
8n+5q <$26