Find the slopeintercept equation of the line x3y9 answer is

Find the slope-intercept equation of the line: x+3y=9

answer is slope= -1/3; y-intercept=3

but I dont know the process..

slope-intercept equation of the line: x+3y=9

---> Standard slope intercept form of equation is y = mx+c

where m is slope and c is y intercept.

So, we need to converte the given equation x+3y =9 in the above form.

3y = -x +9

divide both sides by 3

y = -x/3 +3

Comapre with y =mx +c

Slope m = -1/3 ; y intercept c = 3