Respuesta : Explicación paso a paso : A) 2x + y = 15
3x + y = 212x = 15 - yx = (15 - y) / 23(15 - y) / 2 + y = 21(45 - 3y) / 2 + y = 2145 - 3y + 2y = 4245 - y = 42 - y = 42 - 45 - y = - 3y = 32x + 3 = 152x = 15 - 32x = 12x = 12 / 2x = 6B) 3x + 4y = 24
3x - 2y = 63x = 6 + 2yx = (6 + 2y) / 33(6 + 2y) / 3 + 4y = 24(18 + 6y) / 3 + 4y = 2418 + 6y + 12y = 7218 + 18y = 7218y = 72 - 1818y = 54y = 54 / 18y = 33x - 2(3) = 63x - 6 = 63x = 6 + 63x = 12x = 12 / 3x = 4C) x + y = 60
3x + 9y = 30 - 3x - 3y = - 1803x + 9y = 30 - - - - - - - - - - - - - - - - - - 0 + 6y = - 150y = - 253x + 9( - 25) = 303x - 225 = 303x = 255x = 255 / 3x = 85 D) 2x + 3y = 6
8x + y = 12 - 8x - 12y = - 248x + y = 12 - - - - - - - - - - - - - - - - - - - - 0 - 11y = - 12y = 12 / 118x + 12 / 11 = 128x = 12 - 12 / 118x = 120 / 11x = (120 / 11) / 8x = 120 / 88x = 15 / 11.