20 17 the first volume of the seventh grade mathematics winter vacation life instructs homework 14 the answer of the complete square formula refers to the answer of the first grade mathematics winter vacation life instructs homework. A: First, knowledge navigation.

1.a+2ab+ba-2ab+b

The sum of squares of two numbers plus (or minus) twice the product of these two numbers 22 22

Second, lay a solid foundation:

1.B

2.( 1)9a+ 12ab+4b 22(2) 16x+40xy+25y(3)2 1242 1a？ b？ ab(4)4x 2- 12x+9 16255422(5)Mn-2mna+a(6)4x- 12xy+9y(7)Mn-2mn？ n ( 8)m+2mn+n (9)x？ 4y？ 4xy ( 10)9x？ 16y？ 24xy ( 1 1)-m？ 2mn？ n

3.C 4 explosive D 5。 C 6。 A seven. D 8。 B

9.4y -2ab 3ab

10.( 1)3969 (2) 996004

1 1.( 1)5y？ 4xy (2) meters? n？ 2mn (3)a？ 4b？ 4b？ 1 (4)a+2ab+b-9 (5)m？ 8 1? 18m (6)4y

Third, expand the ability:

12. 10

13. 12

14. 12

15.-2

16.2