Answer:
X= -1 and Y= -3
Step-by-step explanation:
x = -1
y= -3
What you need to do it to plug y into an equation.
{y=-x-4
{y=3x
so
-x-4=3x
and plus x on both sides
4x=-4
divide
x=-1
plug x into equation
y=3x
y=3(-1)
y=-3