Mấy bạn làm thiếu rồi
Ta có
\(\left(2x+3\right)^2=25=5^2=\left(-5\right)^2\)
Suy ra \(\left\{{}\begin{matrix}2x+3=5\\2x+3=-5\end{matrix}\right.\)
Suy ra \(\left\{{}\begin{matrix}x=\dfrac{5-3}{2}=1\\x=\dfrac{-5-3}{2}=-4\end{matrix}\right.\)
Vậy x=1 và x=-4
(2x+3)^2=5^2
Suy ra: 2x+3=5, x=4
^-^
\(\left(2x+3\right)^2=5^2\)
\(\Rightarrow2x+3=5\)
\(2x=5-3\)
\(2x=2\)
\(x=1\)
Vậy x = 1
\(\left(2x+3\right)^2=25\)
\(\Rightarrow2x+3=\sqrt{25}=5\)
\(\Rightarrow2x=5-3=2\)
\(\Rightarrow x=2:2=1\)
