题目定义新运算∣a bc d∣=ad+3b−2c\left|\begin{array}{l}a\;\;\;b\\ c\;\;\;d\end{array}\right|=ad+3b-2cabcd=ad+3b−2c,如∣1 53 7∣=1×7+3×5−2×3=7+15−6=16\left|\begin{array}{l}1\;\;\;5\\ 3\;\;\;7\end{array}\right|=1×7+3×5-2×3=7+15-6=161537=1×7+3×5−2×3=7+15−6=16.计算∣57xy−x22xy−3x2+1−xy+x2∣\left|\begin{array}{c}5&7xy-{x}^{2}\\ 2xy-3{x}^{2}+1&-xy+{x}^{2}\end{array}\right|52xy−3x2+17xy−x2−xy+x2的值.知识点：解二元一次方程组——代入消元法章节：方程与不等式 / 二元一次方程组
