thank you!
2006-09-06 23:45:22 · 11 answers · asked by double B 2 in Science & Mathematics ➔ Mathematics
add the 2 ecuations and you get y=-21 => 3x-(-21)=-6 =>
3x=-27 => x=-9
2006-09-06 23:49:22 · answer #1 · answered by Λиδѓεy™ 6 · 0⤊ 2⤋
3x - y = - 6
-3x + 2y = - 15
- - - - - - - - - - - - - - -
y = - 21
Insert the y value into the top equation
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Solving for x
3x - y = - 6
3x - (- 21) = -6
3x + 21 = - 6
3x + 21 - 21 = -6 -21
subtracting - 21 from both sides of the equation
3x = - 27
3x/3 = - 27/3
Dividing 3 from both sides of the equation
x = - 9
Insert the x value into the top equation
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Checking
3x - y = - 6
3(- 9) - (- 21) = - 6
- 27 - ( -21) = - 6
-27 + 21 = - 6
- 6 = - 6
- - - - - - - - - - - - - - - - - - -
-3x + 2y = - 15
-3(- 9) d+ 2(- 21) = - 15
27 + (- 42) = - 15
27 - 42 = - 15
- 15 = - 15
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The answer is:
X = - 9
y = - 21
2006-09-07 08:12:49 · answer #2 · answered by SAMUEL D 7 · 0⤊ 0⤋
add 3x-y = -6 and -3x+2y= -15
3x -y = -6
-3x+2y = -15
y = -21
then substitute the value of y to any of the equations
3x -(-21)= -6
3x + 21 = -6 >>>( subtract 21 on both sides of the equation)
3x = -27 >>>( divide both sides by 3 so that only the variable x wil remain on the left side)
x = -9
2006-09-07 07:27:27 · answer #3 · answered by mark l 1 · 0⤊ 0⤋
3x - y= -6
+ -3x+2y= -15 Cancel 3x and -3x.
____________
y= -21 Substitute y to equation 1.
3x - y = -6
3x - (-21) = -6
3x + 21 = -6
3x = - 6 - 21
3x = -27
3x = -27
___________
x = -9
Solution Set : ( -9 , -21 )
Checking :
3x - y = -6
3(-9) - (-21) = -6
-27 - (-21) = -6
-27 + 21 = -6
-6 = -6
I hope that this will help in your ASSIGNMENT! don't worry, my answer is correct..
2006-09-07 07:14:00 · answer #4 · answered by Purps.. 2 · 0⤊ 0⤋
(1) 3x-y= -6 multiply by 2 (2) 6x -2y = -12
(3) -3x +2y= -15
Now *** (3) and (2)
-3x +2y +6x -2y = -12 -15
eliminate and add to give
3x = -27 therefor x = -9
and Y = -21
2006-09-07 06:53:53 · answer #5 · answered by advent m 3 · 1⤊ 0⤋
3x - y = -6
-3x + 2y = -15
Multiply top by 2
6x - 2y = -12
-3x + 2y = -15
3x = -27
x = -9
3x - y = -6
3(-9) - y = -6
-27 - y = -6
-y = 21
y = -21
ANS : (-9,-21)
2006-09-07 14:28:49 · answer #6 · answered by Sherman81 6 · 0⤊ 0⤋
3X-Y = -6
-3X+2Y = -15
ADD THEM
3X-3X+2Y-Y =- 6-15
Y =- 21
PUT -21 IN OF THE EQUATIONS TO GET
X = -9
2006-09-07 06:47:53 · answer #7 · answered by Morbeous 3 · 2⤊ 0⤋
3x-y=-6 --------(1)
-3x+2y=-15 --------(2)
Add (1) and (2)
y=-21
substitute this 'y' value in
eq - (2)
-3x+2(-21)=-15
-3x-42=-15
-3x=-15+42
-3x=27
x=27/(-3)
x=-9
2006-09-07 07:01:35 · answer #8 · answered by Anonymous · 1⤊ 0⤋
3X-Y=6 ..............(1)
-3X+2Y=-15 .............(2)
ADDING 1&2
WE GET,
Y= -9
SUBSTITUING Y=-9 IN EQUATION (1)
WE GET,
3X+9=-6
3X=-15
X= -5
THEREFORE THE VALUE OF X=-5 AND Y=-9
2006-09-07 07:02:59 · answer #9 · answered by money_rashu22 1 · 0⤊ 1⤋
the question:
3x-y=-6
-3x+2y=-15
3x cancel with -3x...&-y+2y=1y getting:
-y=-6
y=-15
so
y=-21
good luck :)
2006-09-07 07:18:29 · answer #10 · answered by white skull 3 · 0⤊ 0⤋