Question

Solve each system of equations.
1. x-2y+z=8
y-z=4
z=3
I've tried this problem and 2 other problems maybe 10 times each and I just can't figure it out. I don't know what I'm doing wrong. help.

Answer 1

z=3
use this in equation #2
y-3=4
y=7

Answer 2

z=3,y=7
use these in equation #1
x -2(7)+3=8
x-14+3=8
x-11=8
x=19

Answer 3

z=3,y=7,x=19

Answer 4

check...
x - 2y + z = 8
19 - 2(7) + 3 = 8
19 - 14 + 3 = 8
5 + 3 = 8
8 = 8 (correct)
x = 19, y = 7, z = 3

Answer 5

Thank you @d3v13 and @texaschic101
can you help me on 2 others?

Answer 6

what ya got

Answer 7

2x-y+z=15
-6x-y-z=-11
4x-3y-z=0

Answer 8

@texaschic101

Answer 9

z=11
x=1/2
y=-3