M=-4/3 (3,1) i need writing this in point slope form to form an equation explain

Equation of a line : y=mx+b -> y-y1=m*(x-x1)
You have m and the points , just replace
y-1=(-4/3)*(x-3)
y-1=(-4/3)x-(-4)
y-1=(-4/3)x+4
y=(-4/3)x+5

Answer is either b or c