Answer: Choice A.
=====================================================
Explanation:
Every point in the shaded region has an x coordinate that is equal to -7 or smaller.
Example points include
- (-8, 0)
- (-10, 2)
- (-9, -5)
The y coordinate does not matter. All that matters is the x coordinate. The boundary line is the equation x = -7, representing all points that have x coordinate of -7. The solid boundary line says to the reader "any point on this boundary line is part of the shaded region solution set". This inclusion is due to the "or equal to" of the inequality sign.
