Question 1049827
Let the numbers be x and y
x = y+4
x^2-y^2 = 104 Substitute for x:
(y+4)^2-y^2 = 104
Expand the left side with FOIL (First-Outer-Inner-Last)
(y^2+8y+16)-y^2 = 104
8y+(y^2-y^2)+16 = 104
8y+16 = 104
8y  = 88
y = 11 
Since x = y+4 = x = 11+4= 15
Now we have:
y = 11
x = 15
>>>>>>>>>>>>>>>>
Check:
x^2-y^2 = 104
15^2-11^2 = 104
225-121 = 104 Correct
:
John