SOLUTION: solve the system of equations by substitution 5x+y=-4 y=-x

Algebra.Com
Question 422207: solve the system of equations by substitution
5x+y=-4
y=-x

Found 2 solutions by rfer, mananth:
Answer by rfer(16322)   (Show Source): You can put this solution on YOUR website!
5x-x=-4
4x=-4
x=-1
------
5*-1+y=-4
-5+y=-4
y=+1
-------------
proof
y=-x
1=--1

Answer by mananth(16946)   (Show Source): You can put this solution on YOUR website!
5 x + 1 y = -4 .............1

1 y = 0 - -1 x
Plug the value of y in (1)
5x+1(0- x)=-4
5x-x)=-4
5x-1x=-4 0
4x=-4
/4
x=-1
Plug the value of x in (1)
5x+y=-4
5*-1+y=-4
-5+y=-4
1y=1
/1
y=1

RELATED QUESTIONS

solve each system of equations by the substitution method y=5x-3... (answered by Fombitz)
Solve the system of equations by the substitution system. y=5x+1 y=8x+2 (answered by MathLover1)
Solve the system of equations by substitution y = x^2 + 2x - 2 and y - 3x +... (answered by funmath)
Solve the system of equations by substitution y = x^2 + 2x - 2 and y = 3x + 4 (answered by ankor@dixie-net.com)
Solve the system of equation by substitution 5x + y = -4 and y =... (answered by boilpoil)
y=x^2-4 5x+y=20 solve by the following system of... (answered by Fombitz)
Solve the system of equations by substitution: 3x - y = 4 x + 5y =... (answered by lenny460)
Solve the following system of equations by substitution. 5x+y=39 and... (answered by rfer)
Solve the system of linear equations by substitution. Check your solution. y = 2x + 3 (answered by josgarithmetic)