bantu saya dong guys,ini cara mencarinya gimana ya?

(y-y1)/(y2-y1)=(x-x1)/(x2-x1)
(y+3)/(0+3)=(x-0)/(4-0)
4y+12=3x

y-y1=m(x-x1)
y-0=(3/4)(x+6)
4y=3x+18....(B)