Question

Solve the following system of equations.

4x + 7y – 2z = 0
3x – 5y + 3z = 9
3x + 6y – z = 1


Choices:

A.(1, 0, 2)
B.(–1, 0, –2)
C. (1, 0, –2)
D.(–1, 0, 2)

Answer 1

Look at the picture.

Answer: A. (1; 0; 2)

Answer 2

From the given options, y = 0.
Now, from the 2nd and 3rd equations, we have:
3x + 3z = 9 . . . . . . . . (1)
3x - z = 1 . . . . . . . . (2)
(1) - (2) gives: 4z = 8
z = 8/4 = 2
From (2), 3x - 2 = 1
3x = 1 + 2 = 3
x = 3/3 = 1

Therefore, solution is (1, 0, 2)