Use this math trick to square numbers from 50 to 59 in 2 seconds or less. Let us see how the trick works.
Start by writing down the first part of the answer as shown below
502 = 25___
512 = 26___
522 = 27___
532 = 28___
542 = 29___
552 = 30___
562 = 31___
572 = 32___
582 = 33___
592 = 34___
Notice that for 512, all you need to do is to add 1 to 25 to get the first part of the answer
By the same token, for 542, all you need to do is to add 4 to 25 to get the first part of the answer
Now here is how to find the second part of the answer that you will write on the right side of the first part.
Square the number in the ones place. If the number you get after squaring is less than 10, just put a zero on the left.
For example, for 542, square 4. Since 42 = 16, just put 16 next to 29
542 = 2916
For 532, square 3. Since 32 = 9 and 9 is less than 10, just put 09 next to 28
532 = 2809
502 = 2500
512 = 2601
522 = 2704
532 = 2809
542 = 2916
552 = 3025
562 = 3136
572 = 3249
582 = 3364
592 = 3481