SOLUTION: Solve the system by substitution. 2x-y+z=-4 z=5 -2x+3y-z=-10 answers: A). (-8,7,5) B). (-8,-7,5) C). (8,-7,5) D). (-8,-7,-5)

Algebra ->  Linear-equations -> SOLUTION: Solve the system by substitution. 2x-y+z=-4 z=5 -2x+3y-z=-10 answers: A). (-8,7,5) B). (-8,-7,5) C). (8,-7,5) D). (-8,-7,-5)      Log On


   

Question 666683: Solve the system by substitution.
2x-y+z=-4

z=5
-2x+3y-z=-10
answers:
A). (-8,7,5)
B). (-8,-7,5)
C). (8,-7,5)
D). (-8,-7,-5)
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
 

Hi,

2x-y+z=-4    ||  z=5 

-2x+3y-z=-10 ||   z=5 

 

2x - y = -9       2x+=+-9+%2B+y

-2x + 3y = -5    || Adding to eliminate x

     2y = -14

      y = -7  and x = -8    x+=+-16%2F2