3x would have to be equal to something, like X=5, so it would be 3 times by 5 which would equal 15, but X could be any number.
If you mean: -3x+9y = -6 then it is y = 1/3x-2/3
If you mean: 3x-6 = 6 then the value of x is 4
If you mean: y = -3x then the slope is -3 and there is no y intercept
5
If you mean y = 3x-4 then the slope is 3 and the y intercept is -4
If you mean: 9x2+3x-2 = (3x+2)(3x-1) when factored
I think you mean (3x ± 1)^2 = (3x+1)(3x-1)?
If you mean: 3x+12 then it is 3(x+4) when factorized
If you mean: 3x-(2x+4x-6) then 3x-2x-4x+6 simplifies to 6-3x
If you mean: 3x-y = 1 then it is a straight line equation
If you mean: y-3x = 5 then in slope intercept form y = 3x+5
Assuming you mean 3x-20=130 3x=150 x=50
-2
If you mean: 3x+2y = 16 then it is y = -1.5x+8
If you mean: 20 -3x = 14 then the value of x is 2
I not what you mean
If you mean: -3x+9y = -6 then it is y = 1/3x-2/3