Question

Solve for x, y, z:
x+y+z=12
6x-2y-z=16
3x+4y+2z=28

Answer 1

HELP!!!!!

Answer 2

what are you stuck on?

Answer 3

solve the first equation for x and substitute into the last two equations... then solve those two equations for y and z

Answer 4

I don't get any of it.

Answer 5

"solve the first equation for x"

move all the terms without 'x' in them to one side of the equal sign

Answer 6

can you do that?

Answer 7

I know THAT.
x=-y-z+12

Answer 8

great.

Answer 9

6(-y-z+12)-2y-z=16

Answer 10

"substitute into the last two equations."

6x-2y-z=16

- > 6(-y-z+12) -2y-z=16

3x+4y+2z=28

-> 3(-y-z+12) 4y+2z=28

Answer 11

yep

Answer 12

do some basic algebra to simplify... what are you left with?

Answer 13

two equations with two unknowns...

Answer 14

solve them the same way we just 'solved' for x...

Answer 15

solve one equation for z or y.... substitute into the other equation.

Answer 16

what's16-72?

Answer 17

good one.

Answer 18

never mind.

Answer 19

x=4 y=0 z=8

Answer 20

x=4,y=0 & z=8