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X— 3y+z= 6
2x — бу – 2 = -2
—x+y+ 2 = 7​

2 Answers

2 votes

Answer:

x = -7 1/2

y = - 5/2

z = 11

Explanation:

User Gope
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3 votes

Answer:

x = -7 1/2

y = - 5/2

z = 11

Explanation:

x— 3y+z= 6 (1)

2x — бу – 2 = -2 (2) <=> 2x - 6y = -2 + 2 = 0 <=> (2x - 6y)/2 = 0 <=> x - 3y = 0 (4)

—x+y+ 2 = 7​ (3) <=> -x + y = 7 - 2 <=> x - y = -5 (5)

Subtract (5) from (4), we have:

(x - 3y) - (x - y ) = 0 - (-5)

<=> x - 3y - x + y = 5

<=> -2y = 5

<=> y = - 5/2

Replace y with (4), we have x = 3 × (-5/2) = -15/2 (or -7 1/2)

Replace x with -15/2 and y with -5/2 in (1), we have z = 6 - (-15/2 - (-5/2)) = 6 + (15/2 - 5/2) = 6 + 5 = 11

User Haagenti
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