Question

5|x+1| / 2 = 90 /  |x + 1|

Answer 1

\(\dfrac{5\left|x+1\right|}{2}=\dfrac{90}{\left|x+1\right|}\left(x\ne-1\right)\\ \Rightarrow5\left|x+1\right|^2=90\cdot2=180\\ \Rightarrow\left|x+1\right|^2=36\\ \Rightarrow\left|x+1\right|=6\left(\left|x+1\right|>0\right)\\ \Rightarrow\left[{}\begin{matrix}x+1=6\\x+1=-6\end{matrix}\right.\Rightarrow\left[{}\begin{matrix}x=5\\x=-7\end{matrix}\right.\)