Answer:
y = 9
Step-by-step explanation:
The line x = -7 is a vertical line, so the perpendicular line will be horizontal.
Horizontal lines have a slope of 0.
Using this slope and the point given, plug them into y = mx + b to solve for b and create the equation
y = mx + b
9 = 0(4) + b
9 = b
Plug this and the slope into the equation:
y = mx + b
y = 0x + b
y = 9
So, y = 9 is the equation
