Question

tìm x

5+lx+3l=9

Answer 1

|x + 3| = 9 - 5

|x + 3| = 4

x + 3 = \(\pm\) 4

=> x + 3 = 4

x = 4 - 3

x = 1

=> x + 3 = -4

x = -4 - 3 

x = -7

Answer 2

\(\left|x+3\right|=9-5\\ \rightarrow\left|x+3\right|=4\)

\(\Rightarrow\left\{{}\begin{matrix}x+3=4\rightarrow x=4-3\rightarrow x=1\\x+3=-4\rightarrow x=-4-3\rightarrow x=-7\end{matrix}\right.\)

vậy x=1  hoặc x=-7