1) =(2-a)²=4-4a+a²
2) =(-(b+3))² =(b+3)²=b²+6b+9
3) =(4-n)²=16-8n+n²
4) =(-(x+10))² =(x+10)² =x²+20x+100
5) =(-(2x+3y))² =(2x+3y)² =4x² +12xy+9y²
6) =(1/2b -1/3a)² =1/4 b² - 1/3 ab + 1/9 a²
7) = (-(1.3x+6))² =(1.3x+6)² = 1.69x²+15.6x+36
8) = (b/4 -c)² = b²/16 - 1/2 bc +c²