1.去括号化简得:x^2-(m+2)x-p^2+(m+2)p=0,(x+p)(x-p)-(m+2)(x-p)=0,(x-p)(x+p-m-2)=0,x1=p,x2=m-p+2.2.面积S=1/2p(m-p+2)=-1/2p^2+1/2(m+2)p,当p=-b/2a=1/2(m+2),即2p=m+2时,面积最大,最大值是:(4ac-b^2)/4a=(m+2)^2/8
