Question 973995
slope is -9-(-4)/-5-(-7)  or -5/2. This is -2.5

point slope formula 
y-y1= m(x-x1)

y+4 = -2.5 (x+7)   Be very careful about signs here.  You are subtracting a negative.

y+4= -2.5x - 17.5
y=-2.5 x -21.5

{{{graph(300,300,-15,3,-15,5,-2.5x-21.5)}}}