Clue #1: Latitude
According to Trevor The Terrible's treasure map, the first clue will help us find the latitude of the treasure.
Latitude is a measure of how far north or south of the equator something is. A positive number is north of the equator, and a negative number is south of the equator.
All we have to do to find the treasure's latitude is to solve the Magic Square below.
A magic square is a square in which all the numbers in a row add up to the same number as all the numbers in any other row, AND they add up to the same number as any column. AND they add up to the same number as either of the diagonals.
Hm. It looks like there are two numbers missing in the magic square. One in the middle, and one in the corner. Can you figure out what those two missing numbers are?