add the 2nd and 3rd:
y + z = -1 ... #4
Twice the 3rd added to the first:
7y -5z = 29 .... #5
5 times #4 ---> 5y+5z = -5
#5 ---------> 7y - 5z = 29
add them:
12y = 24
y = 2
in #4
2 + z = -1
z = -3
in #1
2x - 2 - 3 = -7
x = -1
x=-1, y=2 , z=-3
Need help on how to solve system of equations 2x - y + z = -7, x - 3y + 4z = -19, and -x + 4y - 3z = 18.
4 answers
We're did you get the 7y-5z=29
And we're did you get the 4 and 5
Not one of these answer help at all