we know that
point A(1,1) C(3,5)
point D(-2,-4) F(0,0)
step 1
find the slope FD
m=(y2-y1)/(x2-x1)------> m=(0+4)/(0+2)----> m=4/2----> m=2
step 2
find the slope AC
m=(y2-y1)/(x2-x1)------> m=(5-1)/(3-1)----> m=4/2-----> m=2
mAC=mFD
the answer is
the slope FD is 2
