(a-b)2=a2-2ab+b2

(7-b)2=±±b±b2

(a-4)2=±a2±a±

(7a-b)2=±*2±**b±b2

(a-4b)2=±a2±*a*+*2

(7-t)2=±±14t±t2

(7-t)*(7-t)=±±14t±t2

(t-7)*(7-t)=±t2±14t±

(2-z)*(2-z)=±±z±z2

(x-7)*(7-x)=±x2±x±

(2ax-bz)*(2ax-bz)=±*()2±**bz±(bz)2

(vt-7up)*(7up-vt)=±(vt)2±*vt*±*()2

(7-z)*(7-z)=±±z±z2

(7-x)*(x-7)=±x2±x±

(7x-bz2)*(7x-bz2)=±*()2±**bz2±(bz2)2

(2dp-t)*(t-2dp)=±t2±*t*±*()2



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