184,501 views
20 votes
20 votes
Find the difference. Express your answer in simple stop form.7s/s2 - 14s + 49 - 49/s2 – 14s + 49

User Birubisht
by
2.7k points

1 Answer

22 votes
22 votes

The expression given is,


(7s)/(s^2-14s+49)-(49)/(s^2-14s+49)

Apply the fraction rule:


\begin{gathered} (a)/(c)-(b)/(c)=(a-b)/(c) \\ =(7s-49)/(s^2-14s+49) \end{gathered}

Factor 7s-49: 7(s-7)


=(7\left(s-7\right))/(s^2-14s+49)
\begin{gathered} Factor: \\ s^2-14s+49=\left(s-7\right)^2 \end{gathered}

Therefore,


(7\left(s-7\right))/(s^2-14s+49)=(7\left(s-7\right))/(\left(s-7\right)^2)

Apply exponent rule:


\begin{gathered} \left(s-7\right)^2=\left(s-7\right)\left(s-7\right) \\ (7\left(s-7\right))/(\left(s-7\right)^2)=(7\left(s-7\right))/(\left(s-7\right)\left(s-7\right)) \end{gathered}

Cancel out factor: s-7


(7)/(s-7)

Hence, the answer is


(7)/(s-7)

User Arno Chauveau
by
3.1k points