`@` `\text {Ans}`
`\downarrow`
`(7x - 11)^2 = 2^5 * 5^2 + 100?`
`=> (7x - 11)^2 = 32*25 + 100`
`=> (7x - 11)^2 = 800 + 100`
`=> (7x - 11)^2 = 900`
`=> (7x - 11)^2 = (+-30)^2`
`=>`\(\left[{}\begin{matrix}7x-11=30\\7x-11=-30\end{matrix}\right.\)
`=>`\(\left[{}\begin{matrix}7x=41\\7x=-19\end{matrix}\right.\)
`=>`\(\left[{}\begin{matrix}x=\dfrac{41}{7}\\x=-\dfrac{19}{7}\end{matrix}\right.\)
Vậy, `x \in`\(\left\{\dfrac{41}{7};-\dfrac{19}{7}\right\}\)
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