solve by addtion. give they -value of the solution: 4x+2y=2 and x-2y =8?
599677
i know how 2 do this.\n4x+2y=2\n x-2y=8\n---------\n5x   =10\n5x=10\nx=10/5\nx=2.\nsubstitute x=2 in any1 of the equations.\nlet us take x-2y=8.\n  2-2y=8\n  -2y=8-2\n  -2y=6\n    y=6/-2\n    y=-3.\n therefore ur x=2 nd y=-3.
90743
Well you must have two equations! If you wanted to say x+4y=16 then just add the two and you'll fing x (4x=10) and then find y from one of them.
752254
Well, let's check if y=4.\nJust replace y with 4\n4(4) + 2(4) = 24\n16 + 8 = 24\n24 = 24 \nThis is equation is true, so you are correct.
763532
put in y=3x-8 in x+y=4 like this\n\nx+(3x-8)=4\n\n4x-8=4\n   +8  +8\n\n4x=12\n/4    /4\n\nx= 3
712820
write them so they can be added top to bottom (i.e. line up the x's, y's, and constants):\n\n4x + 2y = -4\nx - 2y = -3  (we need to rearrange the original equation here to line things up)\n\nnow add top to bottom:\n\n(4x)+(x)  +  (2y)+(-2y)  =  (-4)+(-3)\n5x + 0 = -7\n5x = -7\nx = -7/5\n\nnow plug x in to either equation to solve for y:\n\n2y = -7/5 + 3\n2y = -22/3\ny = -22/6 = -11/3\n\nHope this helps :)
1133153
7 - 2[4-6+2x] - 8+ x=6\n\n7 - 2[-2+2x] - 8 +x =6\n7 + 4 - 4x - 8 + x =6\n3 - 3x = 6\nx = -1\n\nDon't listen to the math goober - plug the value in and check it.
724639
2x-4y = 3.8\n3x - y = 17.7\n\nmultiply second equation by -4 so that when u add them both u will cancel the y's...\n2x-4y = 3.8\n-12x+4y = -70.8\n\nnow add them..\n\n-10x = -67\n     x = 67/10 = 6.7\n\nnow plug this x in for any one of the original equations and solve for y....\n\n2(6.7) - 4y = 3.8\n\n13.4 - 4y = 3.8\n-4y = -9.6\n   y = -9.6/-4 = 2.4\n\nso the solution is (6.7,2.4)
896553
4x^2+8x-x-2\n(4x-1)(x+2)
447914
-4(2x+8)=32\n-8x-32=32\n-8x=64\nx=-8\n\nEDIT: The guy above missed a sign.  Insert -8 into the original equation to see if it checks out (it does).
859744
(x + 4y)(x - 4y)\nI answered 2 of your questions. Do the rest of the questions yourself.
1053464
if you want to simplify it \n\nit is 3x - 4x + 4 = -x + 4
861681
subtract 1st equation from the second:\n  8y^2=32\nso y^2=4, and y = +/- 2\n\nplug back into 1st equation:\n4x^2+4=4\n\n4x^2=0\nx=0
1027274
2x^2 - 2y^2 = 2(x^2 -y^2) = 2(x-y)(x+y)\n-2x^2 + 2xy = -2x(x-y)\nx^2 + xy = x(x+y)\n2(x-y)(x+y)/[-2x(x -y)]/[x(x+y)]\n= 2(x-y)(x+y)/[-2x(x-y)(x)(x+y)]\n= -1/x^2
232592
2x = 3y - 4y + 5 - 2\n2x = -y + 3\n2x + y = 3
1070900
5x - 2y + 4 = 0 (i)\n3x + 2y + 12 = 0 (ii)\n(i) + (ii)\n\n8x + 16 = 0\n8x = -16\nwherefore x = -2\n\nsub x = -2 into eq (i)\n-10 - 2y + 4 = 0\n-6 = 2y\nwherefore y = -3\n\nx = -2 y = -3 wherefore your homework is done
491343
Equations with one variable can be solved with just that equation for example 2x=4 can be simplified to x=2.\n\nAn equation with two variables cannot be solved purely by itself. For example 4x = 2y can only be simplied to 2x = y. You cannot find the values of x and y without a second equation. If you were given the following two equations 4x = 2y and x + y = 3 then you could use them to calculate x = 1 and y = 2.
554172
Um...\n\n2(-X) + 3(-X) + X + 8\n\n-2X - 3X + X + 8\n\n-5X + X + 8\n\n-4X + 8\n\n8 - 4X