(a-b)2=a2-2ab+b2
(4-b)2=±±b±b2
(a-5)2=±a2±a±
(4a-b)2=±*2±**b±b2
(a-5b)2=±a2±*a*+*2
(4-t)2=±±8t±t2
(4-t)*(4-t)=±±8t±t2
(t-4)*(4-t)=±t2±8t±
(18-z)*(18-z)=±±z±z2
(x-8)*(8-x)=±x2±x±
(18ax-bz)*(18ax-bz)=±*()2±**bz±(bz)2
(vt-8up)*(8up-vt)=±(vt)2±*vt*±*()2
(8-z)*(8-z)=±±z±z2
(4-x)*(x-4)=±x2±x±
(8x-bz2)*(8x-bz2)=±*()2±**bz2±(bz2)2
(18dp-t)*(t-18dp)=±t2±*t*±*()2