a2-b2=(a-b)(a+b)

(4-x)*(4+x)=-2

(a-4)*(a+4)=2-

(4-cd)*(4+cd)=-()2

(6b-4)*(6b+4)=*2-

(6b-4)*(6b+4)=(*)2-

(8-m)*(8+m)=-2

(z-8)*(z+8)=2-

(8-cd)*(cd+8)=-()2

(4b-8)*(4b+8)=*2-

(4b-8)*(8+4b)=(*)2-

(6ab-zx)*(zx+6ab)=*()2-()2

(6z+a)*(a-6z)=2-*2

(mlu+6k)*(6k-mlu)=*2-()2

(8bc3-6x)*(6x+8bc3)=*b2c6-*2

(8bc3-6x)*(6x+8bc3)=(*bc3)2-*2


×