let one number = x, let another number = y
x = y + 7 , x + y = 63
Plug in y + 7 for x
(y + 7) + y = 63
Simplify
2y + 7 = 63
Isolate the y. Note the equal sign. What you do to one side you do to the other
2y + 7 (-7) = 63 (-7)
2y = 56
2y/2 = 56/2
y = 28
As you are only asking for one of the numbers, 28 is your answer. The other is 35.
hope this helps
