## teddygirl Group Title plleeeaseee help! Solve using two different methods. Explain which method you found to be more efficient. 1. 3x - 9y = 3 6x - 3y = -24 2. 7x-3y=20 5x+3y=16 3. y= 1/2x - 6 2x +6y=19 2 years ago 2 years ago

1. jhonyy9 Group Title

1 multiplie first equation by -2 so this will be by elimination method -6x +18y =-6 6x -3y = -24 --------------- 0 15y = -30 y= -30/15 = -2 6x -3*(-2) = -24 6x +6 = -24 6x = -30 x= -30/6 = -5 x=-5 y=-2

2. jhonyy9 Group Title

2 by elimination method just you need assuming these two equation 7x-3y=20 5x+3y=16 ------------- 12x 0 =36 x=36/12 =3 x=3 5*3 +3y=16 15 +3y=16 3y=1 y=1/3 x=3 y=1/3

3. jhonyy9 Group Title

3. y=1/2x -6 so than 2y=x-12 so x-2y=12 and 2x+6y=19 so than the sistem will be x-2y=12 2x+6y=19 solve by elimination method so multiplie first equation by -2 ,than will get -2x+4y=-24 2x+6y=19 ------------ assum 0 10y=-5 y= -5/10 =-1/2 x-2y=12 substitute y=-1/2 x-2(-1/2)=12 x+1=12 x=11 x=11 y=-1/2

4. teddygirl Group Title

Those are all elimination methods. I need different methods.