Answer:
Horizontal: y = 9
Vertical: x = 3
Step-by-step explanation:
Any point is given in the form (x,y). The first number is the x and the second number is the y.
Horizontal lines (a left-right line like the horizon) have an equation in the form "y = anumber" This works because a horizontal line has ZERO slope. So there is no x in the equation because--
y = 0x + b
y = b (a number, use the y-number from the point)
A vertical line has undefined slope so you can't even pretend to use a slope equation. A vertical line (up and down) has an equation in the form
"x = anumber" Use the x from the point.
Horizontal line through (3,9) is y=9.
Vertical line through (3,9) is x=3
