5x -3y =13 4x - 3y =11solve by addition please help.......?
86920
5x - 13 =3y , 4x - 11 = 3y\nSubstitue\n5x - 13 = 4x -11\nsubtact 4x\nx - 13 = -11\nadd 13\nx = 2\n\nplug 2 in\n5 * 2 -3y = 13\n10 - 3y = 13\n-3y = 3\ny = -1
162979
From y=-3x-3 and y=x+5 you have -3x-3=x+5 so\n-3x-x=5+3\n-4x=8\nx=-2\nNow y=x+5=-2+5=3\nThe solution is (-2,3).
930601
put -2y=5-3x call it equation {1}\ncall 4x-5y=86 {2}\n\nmultiply all of the terms i {1} by 5\nmultiply all ot the terms in {2) by 2\nthis gives -10y=25-15x {3} &  8x-10y=172 {4}\nyou've got -10y in terms of x in {3}, so just put that into {4}  8x+25-15x=172, -7x=157, \nx = -172/7 sub in to {1} to get y \nman that was ablast from the past, haven't done that for years.
748808
12\n\n3x-1=11\n3x=12\nx=4\n4*2+4=12
859744
(x + 4y)(x - 4y)\nI answered 2 of your questions. Do the rest of the questions yourself.
492288
x=\n3x-3+2x=5x-6-x\n3x+2x-5x+x=-6+3\n1x=-3\nx=-3&#92;1\nx=-3
863984
4x-3+2x=15\n4x+2x-3=15\n4x+2x=15+3\n6x=18\nx=18:6\nx=3\n\n4*3-3+2*3=15\n12-3+6=15\n9+6=15\n15=15 ...so x=3
309995
do this\n9x-3/4y=1  move 9x to other side\n3/4y=-9x+1 get rid of 3/4, by7 multiplying everything by 4/3\ny=-9x*4/3 +1*4/3\ny=-12x+4/3
169953
use first\nand second\nequations\n\n3x+2y-z=8              \n-3x+4y+z=-14           \n____________           \n   6y  = -6              \n  y  = -1               \n                        \nuse first\nand third\nequations\n\n12x+8y-4z=32\nx-3y+4z=-14\n___________\n13x+5y   =18      (next substitute y=-1) \n13x+-5   =18\n13x      =23\nx    = 23/13\n\n\nput x and y back in one of the original equations:\n\n3(23/13)+2(-1)-z=8\n69/13-10        =z\nz    =    69/13-130/13\nz    =  -61/13\n\ntherefore:\n\nx = 23/13\ny = -1\nz = -61/13\n\nthis set of equations was easier than some.  in some, you might need to use all three equations in groups of two to find the first variable.
689072
5x + 3y = 16 ------ equation 1\n\n2x + 3y = 1 ------- equation 2\n2x = 1 - 3y\nLet x = (1-3y) / 2 \n\nReplace x with y in equation 1, and solve y\n\n5 [ (1-3y) / 2 ] + 3y = 16\n5 (1-3y) + 6y = 32\n5 - 15y + 6y = 32\n9y = -27\ny = -3\n\nReplace the value of y to solve x\n \ntherefore x = [ 1 - 3(-3) ] / 2\nx = 10/2 = 5\n\nYou can try and solve the other pair of system using the same basis as above.
791030
3x – 2y = 6\n3x = 6 + 2y\nx = 2 + 2/3y
720107
4x -12y =5...........(1)\n-x +3y = -1..........(2)\n\nMultiplying eq.(2) by 4 and add with eq.(1)\n(4x -12y =5) + (-4x +12y = -4)=\n0 = 1\nwhich is invalid.
789310
Notice the first equation only involves x.\nx - 5 = 6\nAdd 5 to both sides\nx = 11\nNow replace x with 11 in the second equation\n3(11) - 2y = 5\n33 - 2y = 5\n-2y = 5 - 33\n-2y = -28\ny = -28/-2\ny = 14\nAnswer: (11,14)
108580
3x/5-5=13-3x\n3x/5+3x=13+5\n18/5x=18\n18 divided by 18/5x=5x\nx=5
77049
first you have to tell us what you're solving for.(either x or y).\nIf you want to combine like terms u have to add 2y+2y you get 4y,then you try 4y+4x = ?.\nBut you forgot what is equal to if you're solving \nfor the letter x or y
1118001
3x +2(4x - 9) = -7\n3x + 8x - 18 = -7\n 11x = 11\nx = 1\n\ny = 4(1) - 9\ny = -5
731670
(-4x3 + 3x2 - 5) + (x2 - 5x + 6) =\n-4x3 + 3x2 - 5 + x2 - 5x + 6 =\n-4x3 + 4x2 - 5x + 1