2. given 2x2 system
X + y - Z=3
2y + 2z = 6
-2y - Z = -2

Step-by-step explanation:

X + y - Z=3                   (I)

2y + 2z = 6                (II)

-2y - Z = -2          (III)

Multiply equation (III) by 2 and add equation (II) & (III)

(II)         2y + 2z = 6

(III)*2    -4y - 2z = -4        {Now add and z will be eliminated}

            -2y       = 2

                      y = 2/-2

y = -1

Plugin y =-1 in equation (II)

2*(-1) + 2z = 6

-2 +    2z = 6

          2z = 6 + 2

          2z = 8

            z = 8/2

z = 4

Plugin y = -1 & z = 4 in equation(I)

x - 1 - 4  = 3

     x - 5 = 3

          x = 3 + 5

x = 8

step-by-step explanation:

left be aligning the decimal points is required to not required see the number of digits to the right

b

step-by-step explanation:

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