Answer:
-2/3
Explanation:
The gradient of a line is its slope. You can just convert the equation to slope-intercept form (y=mx+b where "m" is the gradient/slope):
3y + 2x = 1
3y = 1 - 2x
y = 1/3 - 2/3x
y = -2/3x + 1/3
So, as we can see, -2/3 is the gradient/slope of the line.