Question

can anyone help me this using elimination, substitution and matrix methods?

Answer 1

sorry meant "or" not all

Answer 2

write it up so we aint got to keep looking back and forth; this old man gets lost easily

Answer 3

{ 6x+2y-4z=-2
{-3x-4y+2z=-5
{ 4x-6y+3z=1

Answer 4

thats better, now i can see it

Answer 5

lets do matrix ...

Answer 6

i tried elimination twice but it keeps coming out wrong

Answer 7

6 2 -4 =-2 ; divide out a 2
-3 -4 +2 =-5
4 -6 +3 =1


3 1 -2 =-1 ; well R1 and R2 are prime for eliminating
-3 -4 +2 =-5
4 -6 +3 =1


3 1 -2 =-1
-3 -4 +2 =-5
-------------
-3 = -6
1y = 2

Answer 8

now lets see what else we can work

3 1 -2 =-1 ; multiply by -4/3 to eliminate the bottom eq
0 1 0 =2
4 -6 +3 =1

-4 -4/3 8/3 =4/3
4 -6(3) 3(3) = 1
-----------------
0 -22/3 17/3 = 7/3 ; times -3/22

0 1 17/22 = 7/22


1 1/3 -2/3 =-1/3
0 1 0 =2
0 1 17/22 = 7/22



-1 0 =-2(22)
1 17/22 = 7/22
------------------
17/22 = -34/22
1 = -34/17 = -2



1 1/3 -2/3 =-1/3
0 1 0 = 2
0 0 1 = -2



1 1/3 -2/3 =-1/3
0 -1/3 0 =-2/3
------------------
1 0 -2/3 = -3/3
0 0 2/3 = -4/3
-------------------
1 0 0 = -7/3


and where did I mess up if any

Answer 9

right here is a miss


0 -22/3 17/3 = 7/3 ; times -3/22

0 1 -17/22 = -7/22

shoulda been negtaive like this

Answer 10

1 1/3 -2/3 =-1/3
0 1 0 =2
0 1 -17/22 = -7/22

0 -1 0 =-2(22)
0 1 -17/22 = -7/22
--------------------
0 -17/22 = -51/22
-22/17 -22/17
------------------
0 0 1 = 51/17

oy thats an ugly number

Answer 11

1 1/3 -2/3 =-1/3
0 1 0 =2
0 0 1 = 51/17


1 1/3 -2/3 =-1/3
0 -1/3 0 =-2/3
------------------
1 0 -2/3 = -3
0 0 2/3 = 51(2)/17(3)
-------------------------
1 0 0 = -1

Answer 12

what do you keep getting ?

Answer 13

http://www.wolframalpha.com/input/?i=solve+6x%2B2y-4z%3D-2+and+-3x-4y%2B2z%3D-5+and+4x-6y%2B3z%3D1

Answer 14

its x,y,z ; 1,2,3

Answer 15

and i need to repractice my matrixes ;)

Answer 16

im confused haha
too many fractions but lets see if i can put it together with what you wrote

Answer 17

we can do it this way.

the first part you did was fine.
that gave us y

not we can do
2(3rd equation)+3(2nd equation)
giving us
17 0 0 = 17
this gives us x as 1

then we can plug x and y into one of the equations giving us z as 3

took me a min haha

Answer 18

now not "not" (3rd line)