Question

Решите систему:
{3х-2у=1
{4х + 8y = 12

{7х - 2y=1
{-2x + 3y=1

Answer 1

Решим методом сложения
$\left \{ {{3x-2y=1 /4} \atop {4x+8y=12 /1}} \right. =\ \textgreater \ \left \{ {{12x-8y=4} \atop {4x+8y=12}} \right.$
16x=16
x=1

3-2y=1
2y=3-1
2y=2
y=1
(1;1)

$\left \{ {{7x-2y=1/3} \atop {-2x+3y=1/2}} \right. =\ \textgreater \ \left \{ {{21x-6y=3} \atop {-4x+6y=2}} \right.$

17x=5
x=$\frac{5}{17}$
$- \frac{10}{17}+3y=1$
$3y=1-(- \frac{10}{17} )$
$y= \frac{9}{17}$
$( \frac{5}{17} ; \frac{9}{17} )$