Are -3.9 and -0.99 on the same side or the opposite side of zero ?

Same side.  Locate -3.9 on the number line.  Then -0.99 is to the right of -3.9, with both numbers being on the same side (that is, on the left side) of zero.

an

y = 6x -3y -12

y +3y +12 = 6x

=> . x = { 2y / 3 +2 } this is equation of line in terms of x

=> . if line meets the x-axis the co-ordinates of meeting point would be ( x , 0 )

=> . x = 2 ( 0 ) / 3 + 2

=> . x = 2

so, the point is ( 2 , 0 )

6mm^3 or .6cm^3

      216

      /   \

  36     6

  /   \     /

6     6   6

factor trees are nice.