What is the equation of the solid boundary line?
and can you explain how you solved it?

Answer:
solid boundary line: y = -1/2 x + 4
shaded area: y ≥ -1/2 x + 4 and y < x+1
Step-by-step explanation:
solid boundary line pass (0,4) (2,3)
slope (m) = (3-4) / (2-0) = -1/2
y intercept (b) = 4
equation: y = mx + b y = -1/2 x + 4
system: y ≥ -1/2 x + 4
dotted line: (0,1) (2,3)
m = (3-1) / (2-0) = 1
b = 1
equation: y = x + 1
system: y < x+1