I'll have a go at explaining. Brackets is the number in the triangle. The numbers after are those in the row/column leading from it.

If you have this: (9) and then after it, a 4 and a missing number, the missing number would be 5. To make 9.

But the destiny quest puzzle has modifiers. So the number is less the modifier.

Take the above example. If they were on the second row then they would have +2. It would display as: (9) and then 2 and a missing number. The missing number would then become 3.

The calculation is: 9 = (2+2) + (3+2)

You need to calculate the numbers for the three symbols and put them in order as they are shown at the top of the stone. GL!