Question

Usando o método de determinantes resolva:

a)2x+y=-1
-3x+2y=9

b) -x+2y=-3
2x+4y=14

Answer 1

a) 2x + y = -1   x(-2) ⇒ -4x - 2y = 2     b) -x + 2y = -3   x(-2) ⇒ 2x - 4y = 6
   -3x + 2y = 9                                          2x + 4y = 14
-7x = 11                                               4x = 20
x = -11/7                                              x = 5
y = 15/7                                               y = 1