Prosze o pomoc ! : )   D ) { 3s + 5t = - 6 1,5 s - 2t = 3   E ) { 5 = 3x - y 5x -2y= 7   F ) { x -3y =5 y + 3x = -5     TEMAT TO : Rozwiązywanie układów równań metodą przeciwnych współczynników . DAM NAJ !

d) 3s+5t=-6 1,5s-2t=3 |*-2   3s+5t=-6 -3s+4t=-6 - sumujemy   0s+9t=-12 t=-4/3 s=(-6+20/3)*3=-18+20=2   E ) 3x - y = 5 |*-2 5x -2y= 7   -6x +2y = -10 5x - 2y = 7   -x = -3 x=3 15-2y=7 y=4   F ) x -3y =5 y + 3x = -5   x - 3y = 5|*-3 3x + y = -5   -3x +9y = -15 3x + y= -5 10y=-20 y=-2 x=-1

3s + 5t = - 6                                       1,5 s - 2t = 3 1,5 s - 2t = 3 / * (-2)                           t=2,6666666 3s+5t=-6                                            1,5s-2,66666=3 -3s+4t=-6                                            1,5s=6,66666666 / : 1,5 3s-3s+4t+5t=-6+(-6)                              s= 4 i cztery dziewiąte 9t=-12 / :9                                           t=1 i jedna trzecia t=1 i jedna trzecia     5 = 3x - y                                       5 = 3x - y 5x -2y= 7                                       x=3 3x-y=5 / *(-2)                                 5= 3*3-y 5x -2y= 7                                        5=9-y -6x+2y=-10                                     5-9=-y 5x -2y= 7                                        -4=-y -6x+5x+2y-2y=-10+7                        y=4 -x=-3                                              x=3 x=3     x -3y =5 / * (-3)                                     y+3x=-5 y + 3x = -5                                            y=-2 -3x+9y=-15                                            -2+3x=-5 y + 3x = -5                                              3x=-3 /:3 -3x+3x+9y+y=-5+(-15)                             x=-1 10y=-20                                                  y=-2 y=-2