Question

A solução do sistema:
{2x+y=10
{X+3y=15

A)x=1 e y=-5
B)x=4 e y=3
C)x=4 e y=2
D)x=3 e y=4

Answer 1

(I) -2(II)

2x -2x +y -6y = 10 -30

-5y = -20   *(-1)

y = 20/5

y = 4

2x = 10 -4

x = 6/2

x = 3

$\boxed{\underline{\mathbf{R}\mathsf{esposta\to (d) }}}$