Question

Please help, medals will be given!!!
Solve
x + 2y – z = 0
2x + 5y + z = 3
3x – y + z = 29
What is the value of x?

Answer 1

we can use eq1 to eliminate the z parts, then it reduces to 2 eqs in x and y

Answer 2

All you are doing is bringing everything to the other side of the = sine

Answer 3

So the first one would be x=0+z-2y

Answer 4

The answer choices are just single numbers.....

Answer 5

bean seems to be suggesting a substituion method ... while mine is an elimination method

Answer 6

Can you post the answer choices?

Answer 7

the study part of this would be to address what thoughts maria may have on a solution process.

Answer 8

Yes that sounds like a good idea I was going to help her solve the first one so she knew how to do it.

Answer 9

Its a hidden message assignment but the answers left are: 28,14,-2,-4,5,-5,-3,-10,6,and 8

Answer 10

If anyone goes to k12 its the unit 2 extracredit assignment for algebra 2, mrs. shuler....

Answer 11

so what have you tried in working a solution?

Answer 12

elimination i think

Answer 13

elimination is a valid approach :) can you write up what your steps were? i can verify your attempts and correct them if need be

Answer 14

I didn't know where to begin on this one, the last one I did was two equation not three.

Answer 15

thats fine, one thing i notice is that the first equation has a -z while the others have a +z

we can use the first equation to produce 2 new equations that have the z parts eliminated

Answer 16

If you combine each equation like
x+2y - z = 0
2x+5y+z = 3
_________________
Did you learn any thing like this?

Answer 17

x + 2y – z = 0
2x + 5y + z = 3
---------------
3x +7y +0 = 3


x + 2y – z = 0
3x – y + z = 29
----------------
4x +y + 0 = 29


now this should be something you are used to dealing with:

3x + 7y = 3
4x + y = 29

Answer 18

so you do the first one seperatly with the other two??

Answer 19

yes

Answer 20

okay

Answer 21

would you agree that the new setup in xy, we can eliminate the y parts fairly easily?

-7 times eq2 should do it

Answer 22

then what

Answer 23

then you eliminate the ys when you add the results .... that is the elimination process after all

Answer 24

or if substitution is more your style, thats fine too .... the answer doesnt change

Answer 25

so 8?

Answer 26

let me check :)

Answer 27

i get 8 as well

Answer 28

yay!

Answer 29

Thanks have a nice day!

Answer 30

good luck ;)