Sustems of Equations

[ocgirl83]

2. x -3y =7
-3x + 4y = -1

17. -5x +2y + z= 5
-3x - 2y -z =3
-x + 6y =1

37. 2x- 3y =-2
x +y - 4z = -16
3x - 2y + z =7

 

[Denis]

2. x -3y =7
-3x + 4y = -1
17. -5x +2y + z= 5
-3x - 2y -z =3
-x + 6y =1
37. 2x- 3y =-2
x +y - 4z = -16
3x - 2y + z =7

So? Too tired or busy to do your homework?

 

[ocgirl83]

No its not that, i just missed that class and dont understand what the book is trying to say.

 

[cvandoren]

2. x -3y =7
-3x + 4y = -1
17. -5x +2y + z= 5
-3x - 2y -z =3
-x + 6y =1
37. 2x- 3y =-2
x +y - 4z = -16
3x - 2y + z =7

So? Too tired or busy to do your homework?

Please show some type of work so people can help you

 

[ocgirl83]

all i know is that you have to use different systems, for example substition, elimination, etc.

 

[tkhunny]

Well, what's stopping you?

x -3y =7
-3x + 4y = -1

x = 7 + 3y
Now Substitute.
-3(7 + 3y) + 4y = -1

You do the rest.

OR

x -3y =7
-3x + 4y = -1
Multiply the first by 3
3x-9y=21
Now add this to the second

You do the rest.

 

[ocgirl83]

i got y=4 , but the answers in my book have like 4 sets of 2 numbers. so what would the other numbers be?

 

[stapel]

i got y=4 , but the answers in my book have like 4 sets of 2 numbers. so what would the other numbers be?

You've posted three exercises and no work, and now are making cryptic comments regarding... something or other from your book.

At the very least, you need to tell us to which of the exercises "y = 4" is supposed to apply. :roll:

Eliz.

 

[ocgirl83]

y=4 applies to the problem that is x-3y=7 & -3x +4y =-1

 

[stapel]

...and the "four sets of two numbers" thing from the book...?

We can't see your book, so you'll have to tell us what you're talking about. Quoting the "four sets of two numbers" might be a good way to start. Telling us how you got "y = 4" would also be helpful.

Thank you.

Eliz.