题目

在显微镜下观察临时装片时,见物像偏上、偏右,为使物像在中央,应将装片( ) A.往下、往右移  B.往上、往右移   C.往下、往左移   D.往上、往左移 答案：B7．下列四组值中不是二元一次方程y=2x+1的解的是（　　）A．$\left\{\begin{array}{l}{x=0}\\{y=1}\end{array}\right.$B．$\left\{\begin{array}{l}{x=1}\\{y=3}\end{array}\right.$C．$\left\{\begin{array}{l}{x=-\frac{1}{2}}\\{y=0}\end{array}\right.$D．$\left\{\begin{array}{l}{x=-1}\\{y=1}\end{array}\right.$