2. (х +1)² = 1 + 2х + х²
3. 121–4у² = (11 - 2у)(11+ 2у)
4. (2b + 3а)² = 4b2 + 12аb + 9а²
5. 36 – х² = (6 – х)(6 + х)
6. (7х –3)(7х + 3) = 49х² – 9
7. (6 – 2у)² = 36 - 24у + 4у²
8. (10 + 2а)(2а + 10) =100 +40а + 4а²
9. (8к + 3)² = 64к² + 48к + 9
10. (3 + 2у)(3 + 2у)=9 + 12у + 4у²
11. (1 + х)² = 1 + 2х + х²
12. 4у² + 4у + 1 = (2у + 1)²
13. 9а² – 4b² = (3а - 2b)(3а + 2b)