## AEB047 3 years ago Solve for x, y, z: x+y+z=12 6x-2y-z=16 3x+4y+2z=28

• This Question is Open
1. AEB047

HELP!!!!!

2. _irawk_

what are you stuck on?

3. Algebraic!

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

4. AEB047

I don't get any of it.

5. Algebraic!

"solve the first equation for x" move all the terms without 'x' in them to one side of the equal sign

6. Algebraic!

can you do that?

7. AEB047

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

8. Algebraic!

great.

9. AEB047

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

10. Algebraic!

"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

11. Algebraic!

yep

12. Algebraic!

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

13. Algebraic!

two equations with two unknowns...

14. Algebraic!

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

15. Algebraic!

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

16. AEB047

what's16-72?

17. Algebraic!

good one.

18. AEB047

never mind.

19. Arhin

x=4 y=0 z=8

20. jishan

x=4,y=0 & z=8

Find more explanations on OpenStudy