焦点间的距离是4,即|x1-x2|=4图像经过点（2,-3）,即4+2p+q=-3,2p+q=-7x1+x2=-px1x2=q(x1-x2)^2=(x1+x2)^2-4x1x24^2=p^2-4q16=p^2-4(-7-2p)16=p^2+28+8pp^2+8p+12=0(p+2)(p+6)=0p=-2或-6.那么q=-3或5解析式是y=x^2-2x...