Question: how to find the slope and y intercept of y-3=0?
Answer: We begin by isolating the y variable which puts the equation in slope_intercept form y=mx+b where. m= slope. ... 
y−3=0.
y=3.
This equation is is actually y=0x+3.
The slope of this equation is m=0.
The graph of this line is a horizontal line through y=3. A horizontal line has no rise and therefore the slope is zero.