2x+3 / -20 ( / inseamna divide)
2x+3 e D-20 (divizorilor lui -20)
2x+3= (-1, -2, -4, -5, -20)
2x+3=-1 = x=-2
2x+3= -2 = x=-5/2
2x+3= -4 = x= -7/2
2x+3= -5 = x= -4
2x+3= -20 = x= -23/2
Deci B= ( -2, -4)
C= ( (-1, 8), (8, -1), (1,-8), (-8,1), (2, -4), (-4, 2), (4, -2), (-2, 4) )
D= ( -4, -5, -6, -7, 4, 5, 6, 7)