Question

How do you graph y+3=0? On a graph like this

Answer 1

so
y+3=0
subtract 3
y=-3
so since x is not involved,
look at the y axis (vertical) and go up -3 units (go down 3 units)
draw a horizontal line throug that point that is 3 units down
it has to be paralell to the x axis and never cross it