Question

Solve the following system of equations.

2x - 3y + z = -1
2x - 2y - 2z = -8
x + 5y - 3z = 2

Answer 1

2x - 3y + z = -1
2x - 2y - 2z = -8 -->(-1)
-----------------
2x - 3y + z = -1
-2x + 2y + 2z = 8 (result of multiplying by -1)
----------------add
-y + 3z = 7

2x - 2y - 2z = -8
x + 5y - 3z = 2 -->(-2)
---------------
2x - 2y - 2z = -8
-2x - 10y + 6z = -4 (result of multiplying by -2)
---------------add
-12y + 4z = - 12

-y + 3z = 7 -->(-12)
-12y + 4z = -12
----------------
12y - 36z = - 84 (result of multiplying by -12)
-12y + 4z = -12
----------------add
- 32z = - 96
z = -96/-32
z = 3

-y + 3z = 7
-y + 3(3) = 7
-y + 9 = 7
-y = 7 - 9
-y = - 2
y = 2

2x - 3y + z = -1
2x - 3(2) + 3 = -1
2x - 6 + 3 = -1
2x - 3 = -1
2x = -1 + 3
2x = 2
x = 1

check...
x + 5y - 3z = 2
1 + 5(2) - 3(3) = 2
1 + 10 - 9 = 2
11 - 9 = 2
2 = 2 (correct)

x = 1, y = 2, and z = 3

Answer 2

its not really that hard...just time consuming.
Do you have any questions ?