solve for x and y : 2x + y = 3 and x - 3y = 12?

Question

its either
(3,9)
(3,-9)
(3, -3)
(3,3)

Answer 1

Solve for "x" or "y" in either equation. Let's solve "y" in the 1st equation > 2x + y = 3

First: subtract 2x from both sides (when you move a term to the opposite side, always use the opposite sign).

2x - 2x+ y = 3 - 2x
y = 3 - 2x

Sec: replace (3 -2x) with "y" in the 2nd equation.

x - 3(3-2x) = 12
x - 3(3) - 3(-2x) = 12
x - 9 + 6x = 12
7x - 9 = 12 > Add 9 from both sides.
7x - 9+9 = 12+9
7x = 21 > Divide both sides by 7.
7x/7 = 21/7
x = 3

Third: replace 3 with "x" in the 1st equation.

2(3) + y = 3
6 + y = 3 > Subtract 6 from both sides.
6-6 + y = 3-6
y = - 3

Solution (3, -3)

Answer 2

2x+y=3 multiply both sides by 3
6x+3y=9
x-3y=12 add the 2 equations
7x=21 divide both sides by 7
x=3
2x+y=3 substitute 3 for x
2*3+y=3
6+y=3 subtract 6 from each side
y=-3
check
x-3y=12 substitute 3 for x & -3 for y
3-3(-3)=12
3+9=12
12=12

solution is (3, -3)

Answer 3

The answer is (3, -3) assuming it is (X, Y)

2(3) + (-3) = 3 ... 6 - 3 = 3
and
3 - 3(-3) = 12... 3 - (-9) = 12

Answer 4

(2x+y=3) times 3 equals
6x+3y=9
x-3y=12
-----------+
7x=21
x=3
plug it in

2(3)+y=3
6+y=3
y=-3

Answer 5

3, -3 is the answer

Answer 6

6x + 3y = 9
x - 3y = 12-----ADD

7x = 21
x = 3

6 + y = 3
y = - 3

Answer (3, - 3)

Answer 7

It is a simple one?
how ever it is (3,-3)

Answer 8

2x+y=3 x-3y=12
x-3y=12
x=12+3y
2x+y=3
2(12+3y)+y=3
24+6y+y=3
7y=3-24
7y=-21
y=-21/7
y=-3
x-3y=12
x-3(-3)=12
x+9=12
x=12-9
x=3

Answer 9

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