What is the equation of the line with a slope of -1/2 that passes through the point (6,-6) ?

Slop intercept form is y=mx+b
m=slope
b=y intercept

slope is -1/2
y=-1/2x+b
subsitute 6 for x and -6 for y and solve for b
-6=(-1/2(6))+b
-6=-3+b
add 3 to both sides
-3=b

the equation is y=-1/2x-3