Question

What is the solution of the system of equations?

Answer 1

subtracting equation 1 from equation 3 gives 2z = -6
so z = -3

plug this value into equations 1 and 2 will give 2 equations in x and y

Answer 2

can you continue from there?

Answer 3

@Chlorophyll

Answer 4

@sue101 I'd follow exactly @cwrw238 instruction:
Now start with subtract equa. (3) \ (1)

Answer 5

So the point of this problem is that I have to find out what is x y and z right?

Answer 6

Yes, find out the values of whatever variables :)

Answer 7

Alright I think I can do this. I will first do it on a piece of paper then I will type it up on here. Then you see if I am correct. ;) thx

Answer 8

Okie :)

Answer 9

@Chlorophyll

Answer 10

Could you show your work here?

Answer 11

I just add all the x's the y's and the z's... I probably did do it wrong:(

Answer 12

3x + 2y + z = 7 ( 1)
3x + 2y +3z = 1 ( 3)
Subtract them:

Answer 13

ok x + y + 62z

Answer 14

Subtract them vertically:
3x - 3x = 0. 2y - ....?

Answer 15

2y - 2y = 0
z - 3z = -2z

Answer 16

Then 7 - 1 = ...?

Answer 17

-> - 2z = ...?

Answer 18

6

Answer 19

=> z = ....?

Answer 20

i dnt understand ur question :(

Answer 21

Do you understand until this part: - 2z = 6 ?

Answer 22

yes now i have to divide both sides bt -2 to get z alone nd i get -3

Answer 23

That's how cwrw238 wants you to do :)

Answer 24

ah I see so now I plug in -3 for z in the first and second equation.

3x +2y + -3 = 7
-
5x + 5y + 4(=3)

Answer 25

The next step is plug z = -3 into equa. (1) and (2) :

Answer 26

3x + 2y = ...?
5x + 5y = ...?

Answer 27

3x + 5x = 8x
2y + 5y = 7y

Answer 28

3x +2y + -3 = 7
5x + 5y + 4(-3) = 3

Answer 29

-> 3x + 2y = 10
-> 5x + 5y = ...

Answer 30

8x + 7y = 10

Answer 31

Just fill in where the dot is:
5x + 5y + 4(-3) = 3
-> 5x + 5y = ...?

Answer 32

7?

Answer 33

5x + 5y + 4(-3) = 3
-> 5x + 5y = 3 + 12 = ...?

Answer 34

15

Answer 35

> 3x + 2y = 10
-> 5x + 5y = 15 or x + y = 3

Answer 36

Now solve for x and y, can you?

Answer 37

ok do I subtract both of these??

Answer 38

x + y = 3 (1)
3x + 2y = 10 (2)
Multiply the first for 2, then subtract

Answer 39

I am soooo lost with this problem im just doing what you are telling me to do but I have no IDEA WHAT IM DOING IM SO FRUSTRATED!!

Answer 40

Read cwrw238 fist post, which is the guide line!

Answer 41

I think i might just pass the question, why do they have to work my brain soo hard for just 2 points!!

Answer 42

You need to relearn and keep practicing of solving the system of equation by elimination or substitution.

Answer 43

This type of solving is foundation of basic algebra. If you don't need algebra so just skip it for the rest of your life :)

Answer 44

I was going to but the teacher stopped me from doing so XD