Posted by **Al** on Friday, September 16, 2011 at 3:20am.

solve equations by elimination

2x-6y=3 (1)

4x+9y=-1 (2)

- Algebra -
**Anonymous**, Friday, September 16, 2011 at 4:00am
Multiply first equation with -2

- 4 x + 12 y = -6

Note that, if you add down, the y's will cancel out.

- 4 x + 12 y = - 6

4 x + 9 y = - 1

( - 4 x + 4 x ) + ( 12 y + 9 y ) = -6 + ( -1 )

0 + 21 y = -6 - 1

21 y = - 7 Diwide both sides with 21

y = - 7 / 21

( Remark: 7 / 21 = 1 / 3 )

y= - 1 / 3

First equation:

2 x - 6 y = 3

2 x - 6 * ( - 1 / 3 ) = 3

2 x + 6 / 3 = 3

2 x + 2 = 3

2 x = 3 - 2

2 x = 1 Divide both sides with 2

x = 1 / 2

x = 1 / 2 , y= - 1 / 3

- Algebra -
**KK**, Friday, September 16, 2011 at 4:05pm
Thank You

## Answer This Question

## Related Questions

- algebra - i need help with these problems (either a solution or how to plug them...
- College Algebra - Please help! x-2y+z=7 2x+y-z=0 3x+2y-2z=-2 a. Solve the above ...
- algebra - 1 Solve the set of linear equations by the matrix method : a+3b+2c=3...
- Math - Please help! x-2y+z=7 2x+y-z=0 3x+2y-2z=-2 a. Solve the above system of ...
- algebra 2 - 3x+y+z=14 -x+2y-3z=-9 5x-y+5z=30 linear equations solve by ...
- ALGEBRA - USE ELIMINATION TO SOLVE THE SYSTEM OF EQUATIONS {3X-2Y+X=9 X-Y+4Z=10 ...
- algebra 1 - 3a+b=52a+5=10use elimination to solve each systems of equations.
- Algebra - Use the elimination method to solve the sysrem of equations a+6b=13 a+...
- Algebra - can you solve this set of equations using the elimination method? 3x+...
- algebra - How to solve the system of equations below using elimination? b = 2a+1...

More Related Questions