2x + 3y = 6
4x - 6y = - 4
2006-07-20 01:38:39 · 7 answers · asked by small 1 in Science & Mathematics ➔ Mathematics
4x + 6y = 12
4x - 6y = -4
8x = 8
x = 1
2(1) + 3y = 6
2 + 3y = 6
3y = 4
y = 1 1/3
2006-07-20 02:52:18 · answer #1 · answered by jimbob 6 · 0⤊ 0⤋
Multiplying the first equation we get
4x+6y = 12
Adding this to the second equation we get
8x = 8
Hence x = 8/8 = 1
Substituting in the first equation we get 2*1+3y=6
Or 3y=6-2
Or y=4/3
Verifying in the second equation, we get 4*1-6*4/3=-4
Left Hand Side =Rright Hand Side
Proved
2006-07-20 08:44:14 · answer #2 · answered by young_friend 5 · 0⤊ 0⤋
Multiply the 1st equation by -2, you get -4x-6y= -12.
Then add the two equations, you will get -12y= -16.
When solving for y, y=4/3
Substitute this y value into the first equation, you will get 2x+4=6.
Rearrange the equation and you will get 2x=2.
Solve for x, x=1.
So... x=1
y=4/3, The solution looks like this: {1,4/3}
2006-07-20 08:58:39 · answer #3 · answered by Amha 1 · 0⤊ 0⤋
Is this for your homework? If so, I think you should state that in your question . . .
To solve simultaneous equations, you can either move terms around so that one equation is in terms of x (or y) and substitute that for x (or y, whichever you did) in the second equation.
In this one, I would double the top equation and add it to the bottom equation.
4x + 6y + (4x - 6y). Thus, you get 8x = 8, and then x = 1. You can solve the rest from there.
2006-07-20 08:44:05 · answer #4 · answered by jshclhn 2 · 0⤊ 0⤋
4x= 6y-4 => 2x= 3y -2. substitue this in the first eqn.
(3y-2) + 3y =6
6y = 8
y=8/6=4/3.
now, 2x = 3(4/3)-2
2x= 2.=> x=`1.
x=1, y=4/3
2006-07-20 08:59:27 · answer #5 · answered by krishna 2 · 0⤊ 0⤋
suggest a simple way.
2x+3y=6 right! 3y=6-2x; 6y=12-4x substitute in second eqution
4x-6y=-4 but as above 6y=12-4x
4x-(12-4x)=-4
4x-12+4x=-4
8x=8
x=1 substitute and get y=4/3
2006-07-20 08:53:20 · answer #6 · answered by openpsychy 6 · 0⤊ 0⤋
x=1
y= 4/3
2006-07-20 08:44:34 · answer #7 · answered by Si 3 · 0⤊ 0⤋