The values of a and b in the expression given are 11 and 7 respectively
Let the numbers be : a and b
The sum of the numbers equals 18 :
The difference of the numbers equal 4 :
From (1):
Substitute the value of a in (3) into (2)
18 - b - b = 4
Collect like terms
18 - 2b = 4
-2b = 4 - 18
-2b = - 14
b = 14 / 2
b = 7
From (3)
Therefore, the values of a and b are 11 and 7 respectively
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