题目

The ______ you are, the______ you can work out the math problems. A . more carefully; more easily B . more carefully; easier C . more careful; easier D . more careful; more easily 答案：D用配方法解方程2x2+3=7x时，方程可变形为（ ）A．（x-）2=B．（x-）2=C．（x-）2=D．（x-）2=