Question

(x+42)²:115=4.115

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Answer 1

\(\left(x+42\right)^2:115=4.115\\ \Rightarrow\left(x+42\right)^2=4.115.115\\ \Rightarrow\left(x+42\right)^2=2^2.115^2\\ \Rightarrow\left(x+42\right)^2=\left(2.115\right)^2\\ \Rightarrow\left(x+42\right)^2=230^2\\ \Rightarrow\left[{}\begin{matrix}x+42=230\\x+42=-230\end{matrix}\right.\\ \Rightarrow\left[{}\begin{matrix}x=188\\x=-272\end{matrix}\right.\)