Thread: Solving a non-linear system, urgent reply needed!

1. Solving a non-linear system, urgent reply needed!

Not sure where to begin on this one. If you tell me how to do this one, it'd help me with the others.

2. Originally Posted by mankvill

Not sure where to begin on this one. If you tell me how to do this one, it'd help me with the others.
Substitute for y in the second equation to get a quadratic equation. Now solve this quadratic and try both roots to get values for y.

Try it

3. Oh yeah, I always forget to do that!

Now I'm having trouble with this!

(x-2)(x-2) doesn't work.
(x+2)(x-2) doesn't work...

4. Wait.

Is there no solution?

5. Sigh...

x^2+ 4x + 1 = - 3

x^2+ 4x + 4 = 0

(x+2)^2 = 0

x = -2

Substiute this value in y = x^2 + 1 = (-2)^2 + 1 = 4+1 = 5

6. Originally Posted by Isomorphism
Sigh...

x^2+ 4x + 1 = - 3

x^2+ 4x + 4 = 0

(x+2)^2 = 0

x = -2

Substiute this value in y = x^2 + 1 = (-2)^2 + 1 = 4+1 = 5
oh, okay. yeah, i'm not good with that.

So is there 1 answer: -2,5?

7. Originally Posted by mankvill
oh, okay. yeah, i'm not good with that.

So is there 1 answer: -2,5?
Yes, after all that working out... you should not be this doubtful

8. I know, I'm just taking a test right now! Gotta be sure.

Thanks!