Can someone me with these?

solve each system of equations. check each answer algebraically.
11. -­6x + 3y = 33
-­4x + y = 16
12. 2y = 5x ­-1
x + y = -­1
13. x + y + z = -­1
2x + 4y + z = 1
x + 2y ­- 3z = ­-3

QUESTION 12

The given equations are;

and

Make y the subject in equation (2).

We put this equation (3) into equation (1) to get;

Expand;

Put into equation (3)

QUESTION 12

The given equations are

and

Make y the subject in equation (2)

Put equation (3) into (1)

Put into equation (3).

QUESTION 13

The given equations are

Make x the subject in equation (3).

Put equation (4) into equation (1)

Put equation (4) into equation (2)

Put z=1 in equation (5)

Put y=2 and z=1 into equation(4)

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step-by-step explanation: