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33 votes
33 votes
PLEASE HELP!!!

Solve.
-2x+3y-z=-2
3x + y = 4
-2y+2z=4
Enter your answer, in the form (x, y, z), in the boxes in simplest terms.

PLEASE HELP!!! Solve. -2x+3y-z=-2 3x + y = 4 -2y+2z=4 Enter your answer, in the form-example-1
User Oskar Hofmann
by
2.5k points

1 Answer

16 votes
16 votes

Explanation:

the second equation gives us right away

y = 4 - 3x

we can use that now in the 3rd equation :

-2(4 - 3x) + 2z = 4

-8 + 6x + 2z = 4

6x + 2z = 12

3x + z = 6

z = 6 - 3x

now we use both in the 1st equation :

-2x + 3(4 - 3x) - (6 - 3x) = -2

-2x + 12 - 9x - 6 + 3x = -2

-8x + 6 = -2

-8x = -8

x = 1

y = 4 - 3x = 4 - 3×1 = 4 - 3 = 1

z = 6 - 3x = 6 - 3×1 = 6 - 3 = 3

so,

(1, 1, 3)

User Ankit Tyagi
by
3.0k points