A. \(\left[\begin{array}{l} y=17 \\ y=-1 \end{array}\right.\)
B. \(\left[\begin{array}{l} y=27 \\ y=-11 \end{array}\right.\)
C. \(\left[\begin{array}{l} y=7 \\ y=-11 \end{array}\right.\)
D. \(\left[\begin{array}{l} y=27 \\ y=11 \end{array}\right.\)
B
Ta có
\(\begin{array}{l} y(y-16)-297=0 \\ \Leftrightarrow y^{2}-16 y-297=0 \\ \Leftrightarrow y^{2}-27 y+11 y-297=0 \\ \Leftrightarrow y(y-27)+11(y-27)=0 \\ \Leftrightarrow(y-27)(y+11)=0 \Leftrightarrow\left[\begin{array}{l} y-27=0 \\ y+11=0 \end{array}\right.\\ \Leftrightarrow\left[\begin{array}{l} y=27 \\ y=-11 \end{array}\right. \end{array}\)
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