A:①③④
B:②③⑤
C:②④⑥
D:①④⑥
Why don't you ask your teacher for help?(改为同义句)
____ask your teacher for help?
已知:抛物线y=ax2+bx﹣3经过点A(7,﹣3),与x轴正半轴交于点B(m,0)、C(6m、0)两点,与y轴交于点D.