Yintercept of line that has a slope of -1/2 and passes through (2,3)

Y=mx+b (slope-intercept form)
m(slope)=-1/2
Passes through (2,3)
Use the point-slope form (y-y1=m(x-x1))
y-3=-1/2(x-2) "plug" the variables with their variables respectively
Y-3=-1/2x-1/2(-2) distribute -1/2
Y-3=-1/2x+1 simplify
Y=-1/2x+4 add 3 to the opposite side to isolate the y value
4 is your answer because b=4 (y-intercept)

Figure it out your self