anonymous
  • anonymous
Solve the system. x1 - 5x2 + 4x3 = -3 2x1 - 7x2 + 3x3 = -2 -2x1 + x2 + 7x3 = -1
Mathematics
  • Stacey Warren - Expert brainly.com
Hey! We 've verified this expert answer for you, click below to unlock the details :)
SOLVED
At vero eos et accusamus et iusto odio dignissimos ducimus qui blanditiis praesentium voluptatum deleniti atque corrupti quos dolores et quas molestias excepturi sint occaecati cupiditate non provident, similique sunt in culpa qui officia deserunt mollitia animi, id est laborum et dolorum fuga. Et harum quidem rerum facilis est et expedita distinctio. Nam libero tempore, cum soluta nobis est eligendi optio cumque nihil impedit quo minus id quod maxime placeat facere possimus, omnis voluptas assumenda est, omnis dolor repellendus. Itaque earum rerum hic tenetur a sapiente delectus, ut aut reiciendis voluptatibus maiores alias consequatur aut perferendis doloribus asperiores repellat.
chestercat
  • chestercat
I got my questions answered at brainly.com in under 10 minutes. Go to brainly.com now for free help!
anonymous
  • anonymous
I know that we are to end up with a matrices in the form of 1 ? ? ? 0 1 ? ? 0 0 1 ?
Hero
  • Hero
@LadyInkblot have you converted the system to a matrix yet?
anonymous
  • anonymous
Yes. It starts out as a matrix of 1 -5 4 -3 2 -7 3 -2 -2 1 7 -1

Looking for something else?

Not the answer you are looking for? Search for more explanations.

More answers

Hero
  • Hero
How far have you gotten with reducing the matrix?
anonymous
  • anonymous
I don't know if this is correct, but so far I have 1 -5 4 -3 0 3 -5 4 0 -10 15 -7
Hero
  • Hero
Looks like you attempted to perform a couple of row operations. Do you remember which row operations you performed?
anonymous
  • anonymous
I preformed (I believe) 2R1 + R3 and -2R1 - R2
Hero
  • Hero
I can double check that for you. In the mean time, do you know how you plan to continue reducing the matrix from here?
anonymous
  • anonymous
I do not know how to proceed, which is why I came here for help ^_^;
Hero
  • Hero
May I suggest a different approach?
anonymous
  • anonymous
I know that I need to get rid of the -10x2, but I'm not sure how to go about it, since I don't want anything to go back into my third row first column spot.
anonymous
  • anonymous
Of course!
Hero
  • Hero
What if, starting with the original matrix, you performed the following operations to start with: R2 + R3, then 2R1 + R2
anonymous
  • anonymous
Just row 2 + row 3? not multiplying anything?
Hero
  • Hero
Yes, actually do R2 + R3, then -2R1 + R2
anonymous
  • anonymous
okay. I'll get back to you in a minute then with my answer...
anonymous
  • anonymous
Okay, so I got 1 -5 4 -3 0 3 -5 0 0 6 -4 -4
anonymous
  • anonymous
But then I'll still have to get rid of the 6 in the third row... so what about 2R2 + r3?
Hero
  • Hero
You should double check your work for those 2 operations.
anonymous
  • anonymous
okay, what's wrong with it?
anonymous
  • anonymous
Okay, I tried again and got something different 1 -5 4 -3 0 3 -5 -8 0 -6 10 -3
Hero
  • Hero
The 1st and 3rd row are correct. The second row has a mistake with the -8
anonymous
  • anonymous
Ah. Would it be a 4?
Hero
  • Hero
Yes
anonymous
  • anonymous
1 -5 4 -3 0 3 -5 4 0 0 0 5
Hero
  • Hero
You're jumping too far ahead.
Hero
  • Hero
Please post just the first two operations.
anonymous
  • anonymous
1 -5 4 -3 0 3 -5 4 0 -6 10 -3
Hero
  • Hero
Okay, yes, and in the next step, you figure out that you have a row of the form 0 0 0 b which is an invalid row.
anonymous
  • anonymous
Yes. What does that mean, an invalid row. 1 -5 4 -3 0 3 -5 4 0 0 0 5
Hero
  • Hero
If you converted the last row back to an algebraic equation, you'd have the form 0x + 0y + 0z = 5 or just 0 = 5, but 0 = 5 is a false statement.
anonymous
  • anonymous
Okay. So what does that mean for the answer to the problem then. Just that the solution is invalid?
Hero
  • Hero
It means the system cannot be solved and therefore has no solution.
anonymous
  • anonymous
Okay, that makes sense. Thank you!
Hero
  • Hero
You're welcome. Great work on your problem.
anonymous
  • anonymous
Thank you!

Looking for something else?

Not the answer you are looking for? Search for more explanations.