Respuesta :
Imagine the digits are A and B (for the mystery number AB)
A + B = 8 [1st equation]
AB - BA = 18
A*10 + B - 10*B - A = 18
9A - 9B = 18 / divide everything by 9
A - B = 2 [2nd equation]
If you add the two equations you get
2A = 10
A = 5
So B = 8 - 5 = 3
So the number is 53
A + B = 8 [1st equation]
AB - BA = 18
A*10 + B - 10*B - A = 18
9A - 9B = 18 / divide everything by 9
A - B = 2 [2nd equation]
If you add the two equations you get
2A = 10
A = 5
So B = 8 - 5 = 3
So the number is 53