Answer:
The answer is: y = 7
Explanation:
For x = 4, it is a vertical line where everything is x = 4. No matter what y is, x always equals 4.
For the line y = 7, it is a horizontal line, perpendicular to the line x = 4. The line y = 7 passes through the point (-1, 7) and all other similar points where y = 7.