Question

`(2/5 -3x)^2 = 9/25`

Answer 1

\(< =>\left(\dfrac{2}{5}-3x\right)^2=\left(\pm\dfrac{3}{5}\right)^2\\ < =>\left\{{}\begin{matrix}\dfrac{2}{5}-3x=\dfrac{3}{5}< =>x=-\dfrac{1}{15}\\\dfrac{2}{5}-3x=-\dfrac{3}{5}< =>x=\dfrac{1}{3}\end{matrix}\right.\)

Answer 2

`(2/5 -3x)^2 = 9/25`

`@TH1:2/5-3x=3/5`

`<=>3x=2/5-3/5`

`<=>3x=(-1)/5`

`<=>x=(-1)/15`

`@TH2:2/5-3x=(-3)/5`

`<=>3x=2/5+3/5`

`<=>3x=1`

`x=1/3`

Answer 3

\(TH1\left(\dfrac{2}{5}-3x\right)^2=\left(\dfrac{3}{5}\right)^2\\ \dfrac{2}{5}-3x=\dfrac{3}{5}\\ 3x=\dfrac{2}{5}-\dfrac{3}{5}\\ 3x=-\dfrac{1}{5}\\ x=\dfrac{1}{5}:3=-\dfrac{1}{15}\\ TH2\left(\dfrac{2}{5}-3x\right)^2=\left(-\dfrac{3}{5}\right)^2\\ \dfrac{2}{5}-3x=\dfrac{3}{5}\\ 3x=\dfrac{2}{5}-\left(-\dfrac{3}{5}\right)\\ 3x=1\\ x=\dfrac{1}{3}\)

Answer 4

`(2/5 -3x)^2 = 9/25`

`(2/5 -3x)^2 = 3/5`

`=> (2/5 - 3x)  =3/5`

`=>`\(\left[{}\begin{matrix}\dfrac{2}{5}-3x=\dfrac{3}{5}\\\dfrac{2}{5}-3x=-\dfrac{3}{5}\end{matrix}\right.\)

`=>`\(\left[{}\begin{matrix}3x=\dfrac{2}{5}-\dfrac{3}{5}\\3x=\dfrac{2}{5}-\left(-\dfrac{3}{5}\right)\end{matrix}\right.\)

`=>`\(\left[{}\begin{matrix}3x=-\dfrac{1}{5}\\3x=1\end{matrix}\right.\)

`=>` \(\left[{}\begin{matrix}x=-\dfrac{1}{5}:3\\x=1:3\end{matrix}\right.\)

`=>` \(\left[{}\begin{matrix}x=-\dfrac{1}{15}\\x=\dfrac{1}{3}\end{matrix}\right.\)

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Answer 5

(2/5 - 3x)² = (3/5)²

=> 2/5 - 3x = \(\pm\) 3/5 

TH1: 2/5 - 3x = 3/5

                 3x = 2/5 - 3/5

                 3x = -1/5

                   x =-1/5 : 3

                   x = -1/5 x 1/3

                   x = -1/15

TH2: 2/5 - 3x = - 3/5

                 3x = 2/5 - (-3/5)

                 3x = 1

                   x = 1 : 3

                   x = 1/3

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Answer 6