x2
x
=0
-6x2+23x
-6x2+23x-20=0
-6x2+23x-17=0
-6x2+23x-15=0
-6x2+23x-10=0
-6x2+23x-7=0
-6x2+23x+4=0
-6x2+23x+13=0
-6x2+23x+18=0
-20
-17
-15
-10
-7
4
13
18