a) 3x + 2y = 13 / * 2 2x + y = 11 /* -3 6x + 4y = 26 -6x - 3y = -33 _______________ y = -7 3x + 2y = 13 2x + y = 11 /* -2 3x + 2y = 13 -2x - 2y = -22 ___________________ x = -9 y = -7 x = -9 b) 5x+3y = 0 -x -2y = 7 / *5 5x+3y = 0 -5x -10y = 35 _______________ -7y = 35 / :-7 y = -5 5x+3y = 0 / *2 -x -2y = 7 / *3 10x + 6y = 0 -3x - 6y = 21 _____________ 7x = 21 /:7 x = 3 y = -5 x = 3
a) 3x + 2y = 13 2x + y = 11 / - 2x 3x + 2y = 13 y = 11 - 2x 3x + 2 (11 - 2x) = 13 3x + 22 - 4x = 13 / - 22 - x = - 9 / : (-1) x = 9 27 + 2y = 13 / - 27 2y = - 14 / : 2 y = - 7 y = - 7 x = 9 _______________ b) 5x+3y = 0 -x -2y = 7 / + 2y 5x+3y = 0 - x = 7 + 2y / * (-1) 5x+3y = 0 x = - 7 - 2y 5(- 7 - 2y) + 3y = 0 - 35 - 10 y + 3y = 0 / + 35 - 7y = 35 / : (-7) y =- 5 5x - 15 = 0 / + 15 5x = 15/ : 5 x =3 x=3 y= - 5
a)3x + 2y = 13 2x + y = 11 3x + 2y = 13 y = 11 - 2x 3x + 2(11 - 2x) = 13 y = 11 - 2x 3x + 22 - 4x = 13 y = 11 - 2x x = 13 - 22 y = 11 - 2x x = - 9 y = 11 - 18 x = - 9 y = - 7 b) 5x+3y = 0 -x -2y = 7 5x + 3y = 0 -x = 7 - 2y // /-1 5x + 3y = 0 x = -7 + 2y 5(-7 + 2y) +3y = 0 x = -7 + 2y -35 +13y = 0 x = -7 + 2y y = 0 x = -7
