题目内容
10.已知|2x-y-3|+(2x+y+11)2=0,则( )| A. | $\left\{\begin{array}{l}{x=2}\\{y=1}\end{array}\right.$ | B. | $\left\{\begin{array}{l}{x=0}\\{y=-3}\end{array}\right.$ | C. | $\left\{\begin{array}{l}{x=-1}\\{y=-5}\end{array}\right.$ | D. | $\left\{\begin{array}{l}{x=-2}\\{y=-7}\end{array}\right.$ |
分析 利用非负数的性质列出方程组,求出方程组的解即可.
解答 解:∵|2x-y-3|+(2x+y+11)2=0,
∴$\left\{\begin{array}{l}{2x-y=3①}\\{2x+y=-11②}\end{array}\right.$,
①+②得:4x=-8,即x=-2,
②-①得:2y=-14,即y=-7,
则方程组的解为$\left\{\begin{array}{l}{x=-2}\\{y=-7}\end{array}\right.$,
故选D.
点评 此题考查了解二元一次方程组,以及非负数的性质,熟练掌握运算法则是解本题的关键.
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