Question

Soluția reală a sistemului
{2x+3y=11
{4x-3y=-5
Este S={(.....,....)}

Answer 1

$\left\{\begin{matrix} 2x + 3y = 11\\ 4x - 3y = - 5\end{matrix}\right.$

$2x + 4x + 3y - 3y = 11 - 5$

$6x = 6 \: | \div 6$

$x = 1\:\in\:\mathbb{R}$

$2x + 3y = 11$

$2 \times 1 + 3y = 11$

$2 + 3y = 11$

$3y = 11 - 2$

$3y = 9 \: | \div 3$

$y = 3\:\in\:\mathbb{R}$

$S=\left \{ (x, y)\right \}$

$S=\left \{ (1,3) \right \}$