Trick to square number b/w 50 and 59

Trick to square number b/w 50 and 59

57^2=?? (calculate in 2 or 3 seconds)

STEP 1: Take the unit place of the number and add it with 25:
25+7=32

STEP 2: Square the unit place digit(make it 2 digit number_ _)
7^2=49 ( it's 2 digit number) 

STEP 3: Then place result of step 2 after result of step 1:
32 and 49=3249


53^2=?? (calculate in 2 or 3 seconds)

STEP 1: Take the unit place of the number and add it with 25:
25+3=28

STEP 2: Square the unit place digit(make it 2 digit number_ _)
3^2=09 ( it's 2 digit number) 

STEP 3: Then place result of step 2 after result of step 1:
28 and 09=2809


56^2=?? (calculate in 2 or 3 seconds)

STEP 1: Take the unit place of a number and add it with 25:
25+6=31

STEP 2: Square the unit place digit(make it 2 digit number_ _)
6^2=36 ( it's 2 digit number) 

STEP 3: Then place result of step 2 after result of step 1:
31 and 36=3136