700/200=7/2 because devide by 100 and then=3 1/2 and half is .5 so=
3.5
ANSWER
The coordinates of the image are (2,2)
EXPLANATION
The mapping for a reflection across the line y=k is :

We want to find the image of the point (2,-4) after a reflection in the line y=-1.
In this case k=-1.

This simplifies to,


Hence the image is (2,2)
Slope of the line
(3-(-5)) / (-5-(-1))
8 / -4
-2
Take the cross product, then normalize the result.

This has norm

and so a unit vector orthogonal to both given vectors is

An equally correct answer would be the negative of this vector, since

.