Question

Решить по формуле Кремера {5x-3y=16 {2x+4y=22{3x+3y=-2{5x-2y=1

Answer 1

1.
Находим определитель системы:
$\Delta=\left[\begin{array}{ccc}5&-3\\2&4\\\end{array}\right] =20-(-6)=26$
$\Delta_x= \left[\begin{array}{ccc}16&-3\\22&4\\\end{array}\right] =64-(-66)=64+66=130$
$x= \frac{\Delta_x}{\Delta} =130/26=5$
$\Delta_y= \left[\begin{array}{ccc}5&16\\2&22\\\end{array}\right]=110-32=78$
$y= \frac{\Delta_y}{\Delta} =78/26=3$

2.
$\Delta= \left[\begin{array}{ccc}3&3\\5&-2\\\end{array}\right] =-6-15=-21$

$\Delta_x=\left[\begin{array}{ccc}-2&3\\1&-2\\\end{array}\right]=4-3=1$
$x=- \frac{1}{21}$
$\Delta_y=\left[\begin{array}{ccc}3&-2\\5&1\\\end{array}\right]=3+10=13$

$y=- \frac{13}{21}$