Posted by **Sam** on Saturday, April 6, 2013 at 6:39pm.

I cannot solve these last three systems. Could you show me the work for them so i understand how to do them.

1)

x-y=1

2x+y=5

3x-4y=2

2)

5x+8y+6z=14

2x+5y+z=12

-3x+6y-12z=20

3)

x^2+2xy-2y^2=-11

x^2+xy-2y^2=-9

- Math Systems -
**Ollie**, Saturday, April 6, 2013 at 6:49pm
problem 1

in the equation x - y = 1, solve for x in terms of y.

replace x in either of the other two equations and you will be able to solve for x. Now, you can go back to any of the three equations and replace x with the value you found and solve for y.

Check that your solution for x and y satisfy all three equations.

- Math Systems - Partial answer -
**Ms. Sue**, Saturday, April 6, 2013 at 6:51pm
1)

x-y=1

x = 1 + y

2x+y=5

2(1 + y) + y = 5

2 + 2y + y = 5

3y = 3

y = 1

3x-4y=2

3x - 4 = 2

3x = 6

x = 2

## Answer this Question

## Related Questions

- algebra - Could you show me how to do these math systems and show your work so i...
- math - i don't understand what to do.if someone can tell me what to do i can try...
- Biology - Which organ systems help deliver oxygen to body cells? I think that ...
- Science - Why do scientists use models of natural systems? a. Scientists use ...
- earth's systems - What are the four earth systems? and how do they interact with...
- SCIENCE!! - what are two examples of these four types of systems? Physical ...
- Algebra 2 - Solving Systems of Equations in Three Variables: 3x+3y-z=-3 -2x-3y+...
- Algebra 2 - Solving Systems of Equations in Three Variables: 3x+4y+z=1 x+3y-z=-2...
- biology 2 - The digestive, circulatory, respiratory, immune, and excretory ...
- biology 2 - The digestive, circulatory, respiratory, immune, and excretory ...

More Related Questions