1. b^2 - 2by + y^2
2 (7 -c)(7+c)
3. x^2 - 20x + 100
4. 4a^2 + 4a + 1
5. (9-b)(9+b)
6. (x+y)^2
7. 9a^2 - 12ab + 4b^2
8. 64-x^2
9. 4y^2 + 4y + 1
10. 4x^2 - 4x + 1
11. 25x^2 - 1
12. 4x^2+12x+9
13. 4x^2-20x+25
14.(25-4a)(25+4a)
15. y^2-16
16. 4-16x^2
17.x^2-2x+1
18. (11-2y)(11+2y)
19. 4b^2+12ab+9a^2
20. (4-x)(4+x)
21.49x^2-9
22.36-24y+4y^2
23.100+40a+4a^2
24.64k^2+48k+9
25.6+12y+4y^2
26.1+2x+x^2
27. (2y+1)^2
28.(3a-2b)(3a+2b)
1. b^2 - 2by + y^2
2 (7 -c)(7+c)
3. x^2 - 20x + 100
4. 4a^2 + 4a + 1
5. (9-b)(9+b)
6. (x+y)^2
7. 9a^2 - 12ab + 4b^2
8. 64-x^2
9. 4y^2 + 4y + 1
10. 4x^2 - 4x + 1
11. 25x^2 - 1
12. 4x^2+12x+9
13. 4x^2-20x+25
14.(25-4a)(25+4a)
15. y^2-16
16. 4-16x^2
17.x^2-2x+1
18. (11-2y)(11+2y)
19. 4b^2+12ab+9a^2
20. (4-x)(4+x)
21.49x^2-9
22.36-24y+4y^2
23.100+40a+4a^2
24.64k^2+48k+9
25.6+12y+4y^2
26.1+2x+x^2
27. (2y+1)^2
28.(3a-2b)(3a+2b)