Squaring a 2-digit Number Ending in 5

STEPS

Choose a 2-digit number ending in 5.
Multiply the first digit by the next consecutive number.
The product is the first two digit: XX__.
The last part of the answer is always 25: __25.

Example

If the number is 35, 3 x 4 = 12 (first digit times next number) : 12__
The last part of the answer is always 25: __25.
So 35 x 35 = 1225