(1 / 2) for a two digit number, the square of the number on the tenth digit is 9 less than the square of the number on the single digit. If you transpose the one digit number and the ten digit number, you will get two digits (1 / 2) for a two digit number, the square of the ten digit number is 9 less than the square of the one digit number. If you transpose the one digit number and the ten digit number, the two digit number obtained is 27 less than the original two digit number. Then, find the original two digit number

(1 / 2) for a two digit number, the square of the number on the tenth digit is 9 less than the square of the number on the single digit. If you transpose the one digit number and the ten digit number, you will get two digits (1 / 2) for a two digit number, the square of the ten digit number is 9 less than the square of the one digit number. If you transpose the one digit number and the ten digit number, the two digit number obtained is 27 less than the original two digit number. Then, find the original two digit number

The number in ten is 9 less than the square of the number in one, so we can know that the number in one is greater than 3
4*4=16 16-9=7 5*5-9=16>9
Therefore, the single digit can only be 4, and the ten digit can only be 7
A: the original number is 74