Answer:
Use Desmos.com/calculator
Explanation:
Remember, y=mx+b
y is equal to any given y point
x is equal to any given x point
m is equal to slope
b is equal to the y-intercept, or where x = 0 and the line crosses the horizon line.
In order to graph the line correctly, you have to isolate y.
y+x=-3
y=-x-3 would be equal to y=mx+b format
slope is negative 1
y intercept is negative 3
start on the y line, go to (0,-3) and start your line.
slope is negative 1, so you go down one and right one.