SOLUTION: Solve the system by graphing.4x + 2y = 10 Solve the system by substitution. 3x – y = –7 x + y = –9

Algebra.Com
Question 113959:

Solve the system by graphing.4x + 2y = 10
Solve the system by substitution. 3x – y = –7
x + y = –9

Answer by checkley71(8403)   (Show Source): You can put this solution on YOUR website!
4X+2Y=10
2Y=-4X+10
Y=-4X/2+10/2
Y=-2X+5
(graph 300x200 pixels, x from -6 to 5, y from -10 to 10, y = -2x +5).
----------------------------------------------------------------------
3X-Y=-7
X+Y=-9
----------- NOW ADD.
4X=-16
X=16/-4
X=-4 ANSWER.
3*-4-Y=-7
-12-Y=-7
-Y=-7+12
-Y=5
Y=-5 ANSWER.
PROOF
-4+(-5)=-9
-4-5=-9
-9=-9

RELATED QUESTIONS

Solve the system by graphing. 4x+2y=10... (answered by bucky)
Solve the system by graphing. 4x + 2y = 10 y = 4 (answered by Edwin McCravy)
Solve the system by graphing. 4x + 2y = 10 y = 4 (answered by praseenakos@yahoo.com)
slove the system of equations by graphing then classify the system. y + -x -10 4x... (answered by solver91311)
solve system by substitution, x+2y=6... (answered by BrittanyM)
Please help. Solve the system by substitution. 4x+2y=8 y=-3x+7 Thanks... (answered by jim_thompson5910)
Solve the system of linear equations by graphing, substitution, or elimination. y = 5x (answered by Alan3354)
Solve the system by addition -5x+2y=10 x-3y=11 Solve by substitution 2x+2y=0... (answered by checkley71)
Solve the system by substitution. 3x – y = –7 (answered by stanbon)