The answer is 5.5.
hope this helps!!
Yes, your answer is correct
2x + 3y = -6 (Subtract 2x from both sides)
3y = -2x - 6 (Divide both sides by 3 to isolate x) which will give you y = -2/3x - 2 and this graphed would cross the x-axis at (-3,0) and the y-axis at (0, -2). So a + b = -5