Solve each system of equations by the substitution method 3x+4=-y; 2x + y=0

Step-by-step explanation:

3x+4=-y

3x+4+y=-y+y (Add y to both sides)

3x+y+4=0

3x+y+4+-3x=0+-3x (Add - 3x to both sides)

y+4=-3x

y+4+-4=-3x+-4 (Add - 4 to both sides)

y=-3x-4

Step: Substitute-3x-4foryin2x+y=0:

2x+y=0

2x+-3x-4=0

-x-4=0 (Simplify both sides of the equation)

-x-4+4=0+4 (Add 4 to both sides)

-x=4

-x

-1

=

4

-1

(Divide both sides by - 1)

x=-4

Step: Substitute-4forxiny=-3x-4:

y=-3x-4

y = (-3) (-4) - 4

y=8 (Simplify both sides of the equation)

Answer:

x=-4 and y=8