the correct question is
(7s)/(s^2 - 14s + 49) - (49)/(s^2 - 14s + 49)
----- > (7s-49)/(s^2 - 14s + 49)
s^2 - 14s + 49------------ > solving the quadratic equation
s1=7 s2=7 ------------> see the attached figure
therefore
s^2 - 14s + 49=(s-7)(s-7)=(s-7)²
substituting
(7s-49)/(s^2 - 14s + 49)=(7s-49)/(s-7)²=7[s-7]/[(s-7)²]------ > 1/(s-7)
the answer is 1/(s-7)