Question

Sobre sistema LINEAR

3x+y= -2
4x-2y=1

Answer 1

Calcular pelo método da adição

$3x+y=-2~~(I) \\ 4x-2y=1~~(II) \\ \\ multiplicar~~(I)~~por~~(2)~~cancelar~~y~~e~~somar \\ \\ 6x+2y=-4 \\ 4x-2y=1 \\ ------ \\ 10x=-3 \\ \\ x=- \frac{3}{10} \\ \\ substituir~~x~~em \\ \\ 3x+y=-2 \\ 3(- \frac{3}{10} )+y=-2 \\ \\ - \frac{9}{10} +y=-2 \\ \\ -9+10y=-20 \\ 10y=-20+9 \\ 10y=-11 \\ \\ y=- \frac{11}{10} \\ \\ S=\{(- \frac{3}{10} ,- \frac{11}{10} )\}$