2. The matters needing attention of mathematical formula are as follows:
Write the first addend on the top line first. If the two addends are different, write the number with more digits first.
Write the second addend on the next line. If the two addends are different, write the number with fewer digits.
Write "+"before the second number.
The "=" sign in the formula is indicated by a horizontal line and written below the second number.
The calculation results of two numbers are written below the horizontal line and aligned with the numbers above.