Which system of equations has a solution of (1,2,3) ОА.
1 + y + 2z = 9
21 + 2y + 3z = 15
1 - 2 = -2
OB.
I + y = 3
y - 2 = 1
I + y + z = 0
Ос.
-21 - 2z = -8
y + 3z = 7
I + y - 3z = -3
D. -35 + 2y + z = 4
I-y + 2z = 5
s-y-2=-2
Please someone for the love of god help me

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Write an expression to represent the perimeter 2a-3 , 3a+1 , 2a

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