1. = (a + 2b)²
2. = (a + 4)²
3. = (4a + 3b)²
4. = (3x + 7y)²
5. = (3m - n)²
6. = (100 - 1)² =100² - 2*100*1 + 1 = 10000 - 200 + 1 = 9801
7. = (70-3)² = 70² - 2*70*3 + 3² = 4900 - 420 + 9 = 4489
8. = (50 - 2)² = 50² - 2*50*2 + 2² = 2500 - 200 + 4 =2304
9. = (60 - 4)² = 60² - 2*60*4 + 4² = 3600 - 480 + 16 =3120 + 16 = 3136
10. = (80 - 2)² = 80² - 2*80*2 + 2² = 6400 - 320 + 4 = 6084
11. = (5 + 3)² = 8² = 64
12. = (7-3)² = 4² = 16
13. = (4 + 6)² = 10² = 100
14. = (3 - 8)² = (-4)² = 4² = 16
15. = (6 + 9)² =15² = 225