How to graph the equation y = - x - 3 ?

graph{y=-x-3 [-10, 10, -5, 5]}
You can therefore substitute any number for x. So let's substitute 0 for x.
y = - (0) - 3
y = -0 - 3
y = -3
Now, you should also remember to distribute the negative sign, otherwise, you will receive incorrect values. Let plug another number in such as -3
y = -(-3) - 3
y = 3 - 3
y = 0
Likewise, if you plug in a negative number for x, do recall the rule that a negative number times a negative number gives you a positive number then you subtract 3.