Question

slope intercept form of x + 3y + -6

Answer 1

assuming the 2nd "+" to be "=" (forgot to shift key) and you meant

x + 3y = -6

rearrange terms to get y on the left

3y = -x-6
now divide by 3 to get
y = -1/3 x - 2

slope is -1/3
intercept is -2