A.a2+b2=(a+b) | B.-x2-2xy-y2=-(x+y)2 |
C.-a2-b2=(a+b)(a-b) | D.a2-b2=(a+b)(a-b) |
3 |
2 |
A.(a+2b)(b+2) | B.(a-2b)(-a+2b) | C.(a-2b)(-a-2b) | D.(a-2b)(2b-a) |
A.(a+b)(-a-b)=a2-b2 |
B.x2-6x-9=(x-3)2 |
C.x4-16=(x2+4)(x2-4) |
D.(-2m+5n)2=4m2-20mn+25n2 |
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