I WILL MARK BRAINEST!!
Could someone help me with this please, thanks!

Answer:a
a=y
Step-by-step explanation:
Horizontal line (Coordinate Geometry) Definition: A straight line on the coordinate plane where all points on the line have the same y-coordinate. ... A horizontal line is one the goes left-to-right, parallel to the x-axis of the coordinate plane. All points on the line will have the same y-coordinate.
Answer:
a) y-coordinates
b) undefined
c) x=8
d) y= x-6
e) y= -2x+9
2. y=6x+17
Step-by-step explanation:
2. y=mx+b use point (-2,5) and slope to find b
5=6(-2)+b
5=-12+b
5+12=b
b=17
y=6x+17