Rozwiąż układ równań : DAM NAJ ! a) X = 2x + 3y - 1 5 = x + 4y b) x - 3y = 1 - x - y 2x + y = -1

a) x = 2x + 3y - 1 5 = x + 4y -x - 3y = -1 -x - 4y = -5  |* (-1)    -x - 3y = -1    x + 4y = 5 + -------------------------------            y  =  4 x + 4y = 5 x + 16 = 5 x = 5 - 16 x = -11 [latex] left { {{x=-11} atop {y=4}} ight. [/latex] b) x - 3y = 1 - x - y 2x + y = -1 2x - 2y = 1 2x + y = -1  |*2   2x - 2y = 1   4x + 2y = -2 +---------------------    6x      =    -1 6x = -1 x = [latex]- frac{1}{6} [/latex] 2x - 2y = 1 [latex] frac{2}{6} [/latex] - 2y = 1 -2y = 1 - [latex] frac{2}{6} [/latex] -2y = [latex] frac{1}{3} [/latex] 2y = [latex]- frac{1}{3} [/latex] y = [latex] - frac{1}{6} [/latex] [latex] left { {{x= frac{1}{6} } atop {y=- frac{1}{6} }} ight. [/latex] Mam nadzieję że jese dobrze.