The second of two numbers is the first diminished my 6. Their sum is 12. Find the numbers.
Let's call the first number " f " and the second number " s " . We know...
s = f - 6
and
s + f = 12
Plug in f - 6 for s into the second equation.
(f - 6) + f = 12
2f - 6 = 12
2f = 18
f = 9 Use this value for f in the first equation to find s .
s = f - 6 = 9 - 6 = 3