Question

can you please explain this? I mean how you do the diagonal method for a number.
a.k.a this box​

Answer 1

Step-by-step explanation:

Let's start from last box i.e.,the no. in last box is only 1. So,you will write 1 just down the box.

Then, Go to the second box, add the numbers that lies diagonally i.e.,7+8+7=22, write 22  in front of the second box.

Then, Go to third box, add the no. likewise we have done in the second box i.e.,2+9+2=13, take 2 that is in no.22 at tens place and add it to 13 and the answer will 13+2=15.

Then, Go to the first box, the no. you will write 0 that is in the box and take 1  that is in  15 at tens place and it to 0 and the answer will 0+1=1.

answer is = Square of 39 is 1521