Question

Simutaneosly solve
x-5y-z=13
2x+y+z=0
-3x+y+2z=11

Answer 1

I know how to solve 2 simutaneous equations but no idea about 3

Answer 2

i rather the elimination method :P

Answer 3

ok, so if i help you get 2 equations in x and y only , will you be able to solve the rest ?
1) Add 1st and 2nd equation, what u get ?

Answer 4

3x-4y=13

Answer 5

i just need the steps in which to complete it i think

Answer 6

now multiply 1st equation by 2

Answer 7

6x-8y=26

Answer 8

:O how ?

Answer 9

2x-10y-2z=26

Answer 10

now add it with 3rd equation.....

Answer 11

-x-9y=37
Btw does it matter if you add the 2nd to the 3rd eqution instead of 1st to 3rd?

Answer 12

if you add 2nd and 3rd equation, you could not have eliminated 'z'

Answer 13

now can you find 'x' and 'y' ?

Answer 14

y=-4?

Answer 15

x=-1

Answer 16

yes.

Answer 17

now can u find z ?

Answer 18

mhm... I sub x and y into the 1,2,3 equation?

Answer 19

ok z =6 thank you

Answer 20

yes, correct :) ask if any doubts.