The slop intercept form of the line is
y = mx + c
here m is slop of the line and c is y intercept of the line so our equation is
y = (-1/8)x + c
Now the line passes through the point (9 , -7) so we can insert the (x,y) values into above equation to find the value of c , y intercept of the line.
-7 = (-1/8)9 + c
by solving it for c
-7 = -9/8 + c
we can write it as
c = -7+9/8
c = -5.875
