The larger number is 12 more than the smaller number
[tex]x+12=y[/tex]the sum of the two numbers is 74; therefore,
[tex]x+y=74[/tex]Therefore, we have two equations and two unknowns. We solve them by substitution
Putting in the first into the equation the second gives
[tex]x+(x+12)=74[/tex][tex]2x+12=74[/tex]subtracting 12 from both sides gives
[tex]2x=62[/tex]Dividing both sides by 2 gives
[tex]x=31.[/tex]Hence, the the value of the smaller number is 31
