You can put this solution on YOUR website! let one number be x
other number could be x+13
sum of these two numbers is 51
so x+(x+13)= 51
x+x+13 =51
2x+13 =51
subtract 13 on both sides
2x+13-13=51-13
2x =38
divide with 2 on both sides
x =19
oone number is 19
other number is 19+13 =32
so two numbers are 19,32