Given:
The vertices are d(-10,0), e(-10,2), f(-5,2) and g(-5,0).
To find:
The coordinates of the vertices after reflection over the line x=-2.
Solution:
If figure reflected over the line x=a, then

Here, the figure is reflected over the line x=-2, then

...(i)
Now,
For point d,



Similarly,
For point e,

For point f,

For point g,

Therefore, the coordinates of vertices after a reflection over the line x=-2 are d prime (6,0), e prime (6,2), f prime, (1,2) and g prime (1,0).