Question

how to solve this equation?
5x+4y+6z=5
2x-4y-6z=2
2x+3y+x=9
solve for the x,y and z

Answer 1

have you taken linear algebra yet?

Answer 2

I guess not.. oh this is going to be something very long without matrices..

Answer 3

our lesson is about Solving Systems of Linear Equations by Elimination

Answer 4

Okay let's eliminate one variable. Suppose you solve for 4y in the top equation:
4y = 5 - 6z - 5x
Plug that into the 2nd equation. What do u get?

Answer 5

2x-4y-6z=2
2x - (5 - 6z - 5x) -6z = 2

Answer 6

2x - 5 + 6z + 5x - 6z = 2
2x + 5x -5 = 2
7x = 7
x =1

Answer 7

2x+3y+x=9
2*1 + 3y + 1 = 9
2 + 1 +3y = 9
3 + 3y = 9
3y = 6
y = 2

Answer 8

We have the same lesson

Answer 9

4y = 5 - 6z - 5x
4*2 = 5 - 6z - 5*1
8 = -6z
z = -8/6
z = -4/3 just check my arithmetic..

Answer 10

Are you in fourth year high school?

Answer 11

nope...stll in 2nd year:))

Answer 12

We had a quiz about this little a while ago and i got ZERO even if I know how to do it I just don't know why I can't solve it. I had a perfect score in my seatwork but in my QUIZ it is ZERO what do you think is my problem. my quiz is over 20

Answer 13

bahrom your method is different from my teacher taught us

Answer 14

moongazer then use yours and explain it to colleen.. Ive always used this..

Answer 15

could you teach me?

Answer 16

teach u what? my method?

Answer 17

because I think yours is easier

Answer 18

yup

Answer 19

I will give a sample

Answer 20

i will make a question about this

Answer 21

okay give me an example.. preferably 3 eqns and 3 unknowns.. but works with any # of eqns and unknowns if they are equal to each other that is..