Question

(x+5/2)^2=4/9

Answer 1

`(x+5/2)^2=4/9`

`=>[((x+5/2)^2=(2/3)^2),((x+5/2)^2=(-2/3)^2):}`

`=>[(x+5/2=2/3),(x+5/2=-2/3):}`

`=>[(x=-11/6),(x=-19/6):}`

Answer 2

`(x+5/2)^2 =4/9`

`<=> [(x+5/2=2/3),(x+5/2=-2/3):}`

`<=> [(x=2/3-5/2=4/6-15/6=-11/6),(x=-2/3-5/2=-4/6-15/6=-19/6):}`

Vậy `x in{-11/6;-19/6}`

 

Answer 3

\(\Leftrightarrow\sqrt{\left(x+\dfrac{5}{2}\right)^2}=\sqrt{\dfrac{4}{9}}\)

\(\Leftrightarrow x+\dfrac{5}{2}=\dfrac{2}{3}\)

\(\Leftrightarrow x=\dfrac{2}{3}-\dfrac{5}{2}\)

\(\Leftrightarrow x=-\dfrac{11}{6}\)